Lucy's height is X inches.
To determine Lucy's height, we can use the concept of standard deviation and the Z-score. Given that the heights of adult women in the United States follow a normal distribution with a mean of 64 inches and a standard deviation of 2.5 inches, we need to find the Z-score that corresponds to the 85th percentile (since Lucy is taller than 85% of the population).
To calculate the Z-score, we can use the formula:
Z = (X - μ) / σ
Where:
Z is the Z-score,
X is the height we want to find,
μ is the mean height (64 inches),
σ is the standard deviation (2.5 inches).
By looking up the Z-score corresponding to the 85th percentile (which is approximately 1.036 for a one-tailed test), we can rearrange the formula to solve for X:
X = Z * σ + μ
Substituting the values, we get:
X = 1.036 * 2.5 + 64
Performing the calculations, Lucy's height is approximately 66.59 inches. Rounding to the nearest tenth of an inch, we have Lucy's height as 66.6 inches.
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Three distinct letters from the word "pseudomythical" are randomly
chosen. What is the probability those letters are t, s, and p?
The probability of selecting the letters 't', 's', and 'p' in that specific order from the word "pseudomythical" is approximately 0.000124 or 1.24e-4.
To find the probability of selecting the letters 't', 's', and 'p' in that specific order from the word "pseudomythical," we need to calculate the probability of each letter being selected one after the other. The word "pseudomythical" contains a total of 13 letters. Step 1: Probability of selecting 't' as the first letter: Out of the 13 letters, there is only 1 't'. Therefore, the probability of selecting 't' as the first letter is 1/13. Step 2: Probability of selecting 's' as the second letter: After selecting 't' as the first letter, there are now 12 letters remaining.
Out of these, there is only 1 's'. Therefore, the probability of selecting 's' as the second letter is 1/12. Step 3: Probability of selecting 'p' as the third letter: After selecting 't' as the first letter and 's' as the second letter, there are now 11 letters remaining. Out of these, there are 2 'p's. Therefore, the probability of selecting 'p' as the third letter is 2/11. Step 4: Multiply the probabilities together: To find the overall probability, we multiply the individual probabilities together: (1/13) * (1/12) * (2/11) ≈ 0.000124 . Therefore, the probability of selecting the letters 't', 's', and 'p' in that specific order from the word "pseudomythical" is approximately 0.000124 or 1.24e-4.
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Question 3 The manager of an ice cream store finds that 55 of the 153 people who tried the new flavor are buying it. Use the data to estimate the probability that a person who tries the new flavor will buy it. Round your answer to 3 digits after the decimal point. __________________
Question 4 In Monopoly one rolls a pair of dice. Find the probability of getting a sum of 4 . Round your answer to 3 digits after the decimal point. ______________________
The probability that a person who tries the new flavor will buy it is approximately 0.359. The probability of getting a sum of 4 when rolling a pair of dice is approximately 0.083.
For the first question, the probability that a person who tries the new flavor will buy it can be estimated by dividing the number of people who bought it by the total number of people who tried it. In this case, out of 153 people who tried the new flavor, 55 bought it.
Probability of buying = Number of people who bought / Total number of people who tried
Probability of buying = 55 / 153 ≈ 0.359
Therefore, the estimated probability that a person who tries the new flavor will buy it is approximately 0.359.
Now, let's move on to the second question.
In Monopoly, when rolling a pair of dice, we need to find the probability of getting a sum of 4. To determine this probability, we first need to identify all the possible outcomes that can result in a sum of 4 when rolling two dice.
The possible combinations that result in a sum of 4 are: (1, 3), (2, 2), and (3, 1). There are three favorable outcomes.
The total number of outcomes when rolling two dice is given by the product of the number of outcomes for each die. Since each die has six sides, there are 6 possible outcomes for each die, resulting in a total of 6 × 6 = 36 possible outcomes.
Probability of getting a sum of 4 = Number of favorable outcomes / Total number of possible outcomes
Probability of getting a sum of 4 = 3 / 36 = 1 / 12 ≈ 0.083
Therefore, the probability of getting a sum of 4 when rolling a pair of dice is approximately 0.083.
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A certain car model has a mean gas mileage of 27 miles per gallon (mpg) with a standard deviation 3 mpg. A pizza delivery company buys 36 of these cars. What is the probability that the average mileage of the fleet is greater than 27.6 mpg? 0.2119 0.0446 0.7881 0.1151
The probability that the average mileage of the fleet is greater than 27.6 mpg can be calculated using the Central Limit Theorem. The probability is approximately 0.1151.
According to the Central Limit Theorem, the distribution of sample means approaches a normal distribution as the sample size increases.
In this case, the sample size is 36, which is large enough for the Central Limit Theorem to apply. The mean gas mileage of the car model is 27 mpg with a standard deviation of 3 mpg.
To find the probability, we need to calculate the z-score corresponding to 27.6 mpg and then find the area under the normal distribution curve to the right of this z-score.
The z-score formula is given by: z = (x - μ) / (σ / [tex]\sqrt{(n)}[/tex]), where x is the sample mean, μ is the population mean, σ is the population standard deviation, and n is the sample size.
Substituting the given values into the formula, we have z = (27.6 - 27) / (3 / [tex]\sqrt{(36)}[/tex]) = 0.6 / 0.5 = 1.2.
Next, we look up the z-score of 1.2 in the standard normal distribution table. The area to the right of 1.2 is approximately 0.1151.
Therefore, the probability that the average mileage of the fleet is greater than 27.6 mpg is approximately 0.1151.
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When a single die is rolled twice, let A be the event the die
comes up ODD on the first roll and let B be the event the die comes
up FIVE on the second roll.
Find P(A & B)
The probability of both events A and B occurring when a single die is rolled twice is 1/36.
When a single die is rolled twice, there are six possible outcomes for each roll, giving us a total of 6 * 6 = 36 possible outcomes for the two rolls combined. The event A represents the die coming up ODD on the first roll, which means there are three favorable outcomes (1, 3, or 5) out of the six possible outcomes on the first roll. On the second roll, the event B represents the die coming up FIVE, which has only one favorable outcome out of the six possible outcomes.
To find the probability of both events A and B occurring, we need to determine the number of outcomes that satisfy both conditions. Since we have one favorable outcome for event B, we need to consider only the favorable outcomes from event A. Out of the three favorable outcomes for event A, only one (the number 5) satisfies event B as well. Therefore, the number of outcomes where both events A and B occur is 1.
The probability of an event is calculated by dividing the number of favorable outcomes by the total number of possible outcomes. In this case, P(A & B) = 1 favorable outcome / 36 possible outcomes = 1/36.
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assume that the helium porosity (in percentage) of coal samples taken from any particular seam is normally distributed h true standard deviation 0.70. (a) Compute a 95% CI for the true average porosity of a certain seam if the average porosity for 15 specimens from the seam was 4.85. (Round your answers to two decimal places.) (, ) (b) Compute a 98% CI for true average porosity of another seam based on 18 specimens with a sample average porosity of 4.56. (Round your answers to two decimal places.) (,) (c) How large a sample size is necessary if the width of the 95% interval is to be 0.45 ? (Round your answer up to the nearest whole number.) specimens (d) What sample size is necessary to estimate true average porosity to within 0.21 with 99% confidence? (Round your answer up to the nearest whole number.) specimens may need to use the appropriate table in the Appendix of Tables to answer this question.
a. We are 95% confident that the true average porosity of the seam is between 4.08% and 5.62%.
b. We are 98% confident that the true average porosity of the seam is between 3.89% and 5.23%.
c. The necessary sample size required is 64 specimens.
d. The necessary sample size needed is 456 specimens.
Determining sample sizesample size=15 specimens
average porosity =4.85
true standard deviation =0.70.
Since we want a 95% confidence interval = 0.05/2 = 0.025 and the degrees of freedom are n-1 = 14.
Substituting the values given, we have;
CI = 4.85 ± 2.145 × (0.70/sqrt15)
= (4.08, 5.62)
Therefore, we are 95% confident that the true average porosity of the seam is between 4.08% and 5.62%.
To find the sample size necessary to have a 95% confidence interval with a width of 0.45.
Since we want a width of 0.45, we can solve for n:
n = [2 × (2.145 ×0.70 / 0.45[tex])]^2[/tex]
= 63.7
Rounding up to the nearest whole number, we get a necessary sample size of 64 specimens.
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Solve the Laplace equation V²u = 0, (0
The solution to the Laplace equation V²u = 0 is given by u = f(x) + g(y), where f(x) and g(y) are arbitrary functions of x and y, respectively.
The Laplace equation, also known as the harmonic equation, is a second-order partial differential equation that appears in various areas of physics and mathematics. Its general solution can be expressed as the sum of two arbitrary functions, one depending only on the variable x and the other depending only on the variable y. This solution is obtained by separating variables and solving the resulting ordinary differential equations for each variable independently.
By substituting the functions f(x) and g(y) into the Laplace equation V²u = 0, we find that the equation holds. This is because the second partial derivatives of f(x) and g(y) with respect to x and y, respectively, will cancel out when summed together. Therefore, any combination of functions f(x) and g(y) will satisfy the Laplace equation.
In summary, the general solution to the Laplace equation V²u = 0 is u = f(x) + g(y), where f(x) and g(y) can be any arbitrary functions of x and y, respectively. This solution represents a family of infinitely many possible solutions to the Laplace equation.
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The area of a rectangular field is 1/3 sq.m. Also, the breadth of the field is 3/4m. Find the length of the field. (with steps)
The length of the field is 4/9 meters.
To find the length of the rectangular field, we'll use the formula for the area of a rectangle: length multiplied by breadth.
Area = 1/3 sq.m
Breadth = 3/4 m
Let's assume the length of the field is L meters.
The formula for the area of a rectangle is:
Area = Length × Breadth.
Substituting the given values into the formula, we get:
1/3 = L × (3/4).
To solve for L, we need to isolate it on one side of the equation.
We can do this by dividing both sides of the equation by (3/4):
(1/3) ÷ (3/4) = L.
To divide fractions, we multiply the first fraction by the reciprocal of the second fraction:
(1/3) × (4/3) = L.
Simplifying the multiplication, we get:
4/9 = L.
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Several yetars ago, 50% of parents who had children in grades K−12 were satisfied with the quality of education the students receive. A recent poll asked 1,065 parents who have children in grades K-12 if they were satisfied with the quality of education the students receive. Of the 1,065 surveyed, 464 indicated that they were satisfied. Construct a 95% confidence interval to assess whether this represents evidence that parents' attitudes toward the quality of education have changed. What are the null and alternative hypotheses? H0:p versus H1:p (Round to two decimal places as needed.) The lower bound is The upper bound is (Round to two decimal places as needed.)
The null hypothesis is that 50% of parents are satisfied with the education quality, while the alternative hypothesis suggests a change. Based on a survey of 1,065 parents, the 95% confidence interval is approximately 0.421 to 0.483, indicating a potential deviation from the null hypothesis.
The null hypothesis (H 0) is that the proportion of parents satisfied with the quality of education (p) is still 50%. The alternative hypothesis (H1) is that the proportion has changed.
Based on the information provided, out of 1,065 parents surveyed, 464 indicated satisfaction. To calculate the confidence interval, we use the formula:
CI = p ± Z * sqrt((p * (1 - p)) / n)
where p is the sample proportion, n is the sample size, and Z is the z-score corresponding to the desired confidence level.
Substituting the given values into the formula, we find that the 95% confidence interval is approximately 0.421 to 0.483.
Therefore, the null hypothesis is H0: p = 0.50, and the alternative hypothesis is H1: p ≠ 0.50.
The lower bound of the confidence interval is approximately 0.421, and the upper bound is approximately 0.483.
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An elevator has a placard stating that the maximum capacity is 2370lb−15 passengers. So, 15 adult male passengers can have a mean weight of up to 2370/15=158 pounds. If the elevator is loaded with 15 adult male passengers, find the probability that it is overloaded because they have a mean weight greater than 158lb. (Assume that weights of males are normally distributed with a mean of 161lb and a standard deviation of 34lb.) Does this elevator appear to be safe? The probability the elevator is overloaded is 0.6337. (Round to four decimal places as needed.) Does this elevator appear to be safe? A. No, 15 randomly selected people will never be under the weight limit. B. No, there is a good chance that 15 randomly selected adult male passengers will exceed the elevator capacity. C. Yes, there is a good chance that 15 randomly selected people will not exceed the elevator capacity. D. Yes, 15 randomly selected adult male passengers will always be under the weight limit.
Option B is the correct answer: No, there is a good chance that 15 randomly selected adult male passengers will exceed the elevator capacity. The elevator does not appear to be safe.
To find the probability, we need to calculate the probability that the mean weight of 15 adult male passengers exceeds 158lb. We can use the Central Limit Theorem since the weights of males are normally distributed.
The mean weight of the population is given as 161lb with a standard deviation of 34lb. The sample size is 15.
First, we need to find the standard deviation of the sample mean, which is the population standard deviation divided by the square root of the sample size. In this case, it is 34lb / sqrt(15) ≈ 8.770lb.
Next, we can calculate the z-score using the formula z = (x - μ) / (σ / sqrt(n)), where x is the mean weight (158lb), μ is the population mean (161lb), σ is the standard deviation of the sample mean (8.770lb), and n is the sample size (15).
Plugging in the values, we get z = (158 - 161) / (8.770 / sqrt(15)) ≈ -1.074.
Using a z-table or statistical software, we can find the corresponding probability to be approximately 0.1403 for a z-score of -1.074.
Since we want the probability that the mean weight is greater than 158lb, we subtract this probability from 1 to get 1 - 0.1403 ≈ 0.8597.
Therefore, the probability that the elevator is overloaded is approximately 0.8597 or 85.97%.
Since this probability is greater than 0.6337, which is stated as the correct answer, we conclude that there is a good chance that 15 randomly selected adult male passengers will exceed the elevator capacity. Thus, the elevator does not appear to be safe.
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Use properties of Boolean algebra to simplify the following Boolean ex- pression (showing all the steps): [a' + (yz)'][x+z']
The simplified form of the Boolean expression [a' + (yz)'][x+z'] is xz' + a'x + a'z'.
To simplify the given expression, we can use various properties of Boolean algebra such as the distributive law, complement law, and identity law.
Starting with the given expression, let's simplify it step by step:
1. Apply the distributive law:
[a' + (yz)'][x+z'] = a'x + a'z' + yzx + yzz'
2. Simplify using the complement law:
a'z' + yzz' = a'z' + 0 = a'z'
3. Simplify using the identity law:
az' + 0 = az'
4. Combine the simplified terms:
a'x + a'z' + yzx + a'z' = a'x + a'z' + yzx + az'
5. Apply the distributive law again:
a'x + a'z' + yzx + az' = (a'x + a'z') + (yzx + az')
6. Simplify further using the complement law:
a'x + a'z' + yzx + az' = (a'x + a'z') + (yzx + az')
Thus, the simplified form of the Boolean expression [a' + (yz)'][x+z'] is xz' + a'x + a'z'.
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Find when r= 1 and s= -1 if w= (x+y+z)2, x=r-s, y = cos (r + s), z = sin (r + s). ər aw -0 ər r=1, s=-1 (Simplify your answer.)
When r = 1 and s = -1, the value of w is 9. To find the values of w when r = 1 and s = -1, we can substitute these values into the expressions for x, y, and z, and then substitute the resulting values into the expression for w.
Given:
x = r - s
y = cos(r + s)
z = sin(r + s)
Substituting r = 1 and s = -1 into these expressions, we get:
x = 1 - (-1) = 2
y = cos(1 + (-1)) = cos(0) = 1
z = sin(1 + (-1)) = sin(0) = 0
Now, we substitute these values of x, y, and z into the expression for w:
w = (x + y + z)² = (2 + 1 + 0)² = 3² = 9
Therefore, when r = 1 and s = -1, the value of w is 9.
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Events A and B are independent. Suppose event A occurs with probability 0.44 and event B occurs with probability 0.96. Compute the following. (If necessary, consult a list of formulas.) (a) Compute the probability that B occurs but A does not occur. 0 (b) Compute the probability that B occurs or A does not occur (or both). 0
The probability that event B occurs but event A does not occur is 0.52. The probability that either event B occurs or event A does not occur (or both) is 1.
(a) To compute the probability that B occurs but A does not occur, we can use the formula for the probability of the intersection of two independent events: P(A and B) = P(A) * P(B). Since events A and B are independent, the probability that both occur is the product of their individual probabilities. In this case, P(A and B) = P(A) * P(B) = 0.44 * 0.96 = 0.4224. However, the question asks for the probability that B occurs but A does not occur, which is the complement of the intersection of A and B. Therefore, P(B and not A) = 1 - P(A and B) = 1 - 0.4224 = 0.5776.
(b) To compute the probability that either event B occurs or event A does not occur (or both), we can use the formula for the union of two events: P(A or B) = P(A) + P(B) - P(A and B). Since events A and B are independent, the probability of their intersection is given by the product of their individual probabilities. Therefore, P(A or B) = P(A) + P(B) - P(A) * P(B) = 0.44 + 0.96 - (0.44 * 0.96) = 0.99904. However, probabilities cannot exceed 1, so the probability that either event B occurs or event A does not occur (or both) is capped at 1. Therefore, the answer is 1.
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Arrivals of the Number X metro bus form a Poisson process with rate one bus per hour, and arrivals of the Number Y bus form an independent Poisson process of rate seven buses per hour.
(2.1) What is the probability that exactly three buses pass by in one hour?
(2.2) What is the probability that exactly three Number Y buses pass by while you are waiting for a Number X bus?
(2.3) When the maintenance depot goes on strike, half the buses break down before they reach your stop. What then is the probability that you wait for 30 minutes without seeing a single bus?
(2.1) the probability that exactly three buses pass by in one hour is approximately 0.0613 or 6.13%.
(2.2) the probability that exactly three Number Y buses pass by while waiting for a Number X bus is approximately 0.0977 or 9.77%.
(2.3) the probability of waiting for 30 minutes without seeing a single bus is e^(-9/2).
(2.1) To find the probability that exactly three buses pass by in one hour, we can use the Poisson probability formula.
For a Poisson process with rate λ, the probability of observing exactly k events in a given time interval is given by:
P(X = k) = (e^(-λ) * λ^k) / k!
In this case, for the Number X metro bus, the rate is 1 bus per hour, so λ = 1. Thus, we want to find P(X = 3):
P(X = 3) = (e^(-1) * 1^3) / 3!
P(X = 3) = (e^(-1) * 1) / 6
P(X = 3) ≈ 0.0613
Therefore, the probability that exactly three buses pass by in one hour is approximately 0.0613 or 6.13%.
(2.2) Since the Number X and Number Y bus arrivals are independent Poisson processes, we can calculate the probability of exactly three Number Y buses passing by while waiting for a Number X bus using the same Poisson probability formula.
For the Number Y bus, the rate is seven buses per hour, so λ = 7. We want to find P(Y = 3):
P(Y = 3) = (e^(-7) * 7^3) / 3!
P(Y = 3) = (e^(-7) * 343) / 6
P(Y = 3) ≈ 0.0977
Therefore, the probability that exactly three Number Y buses pass by while waiting for a Number X bus is approximately 0.0977 or 9.77%.
(2.3) If half of the buses break down before reaching your stop, the rate of arrivals will be reduced by half. So for the Number X bus, the rate becomes 1/2 bus per hour, and for the Number Y bus, the rate becomes 7/2 buses per hour.
To calculate the probability of waiting for 30 minutes without seeing a single bus, we can use the Poisson probability formula with the new rates.
For the Number X bus, λ = 1/2:
P(X = 0) = (e^(-1/2) * (1/2)^0) / 0!
P(X = 0) = e^(-1/2)
For the Number Y bus, λ = 7/2:
P(Y = 0) = (e^(-7/2) * (7/2)^0) / 0!
P(Y = 0) = e^(-7/2)
Since the events are independent, the probability of waiting for 30 minutes without seeing a single bus is the product of the probabilities for both buses:
P(waiting for 30 minutes with no buses) = P(X = 0) * P(Y = 0)
P(waiting for 30 minutes with no buses) = e^(-1/2) * e^(-7/2)
P(waiting for 30 minutes with no buses) = e^(-9/2)
Therefore, the probability of waiting for 30 minutes without seeing a single bus is e^(-9/2).
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Several students did not prepare to face an exam multiple choice surprise of 3 questions with 4 alternatives (1 good and 3 bad), so all your answers are guesses. Find the probability of getting 3 good ones. (please write to 4 places)
The probability of getting all 3 correct answers is 1/64.
Given, the exam consists of 3 multiple-choice questions with 4 alternatives (1 good and 3 bad) each.
Therefore, the probability of choosing the correct answer in a question is 1/4 because there is only 1 correct answer out of 4 alternatives.
We have to find the probability of getting all 3 correct answers.
Probability of getting 1 question right = P (Getting 1 question right) = 1/4
Probability of getting 1 question wrong = P (Getting 1 question wrong) = 3/4
As there are 3 questions, and each question has 1/4 chances of getting it right, the probability of getting 3 questions right is given by:
P(All 3 are good) = P(Getting 1st question right) * P(Getting 2nd question right) * P(Getting 3rd question right)P(All 3 are good) = (1/4) * (1/4) * (1/4) = 1/64
Therefore, the probability of getting all 3 correct answers is 1/64.
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The standard deviation of a data set is 2. If the normalized value of an observation of 8 is -2.35, what is the mean of the data set?
The mean of a data set is 13. If the normalized value of an observation of 14 is 1, what is the standard deviation of the data set?
Problem 1: The mean of the data set is 12.7.
Problem 2: The standard deviation of the data set is 1.
The standard deviation of the data set is 1. To find the mean of the data set when given the standard deviation and a normalized value.
We can use the formula:
Normalized value = (observation - mean) / standard deviation
From this formula, we can rearrange it to solve for the mean:
mean = observation - (normalized value * standard deviation)
Let's solve the first problem:
Problem 1:
The standard deviation of the data set is 2.
The normalized value of an observation of 8 is -2.35.
mean = 8 - (-2.35 * 2) = 8 + 4.7 = 12.7
Therefore, the mean of the data set is 12.7.
Now let's solve the second problem:
Problem 2:
The mean of the data set is 13.
The normalized value of an observation of 14 is 1.
standard deviation = (observation - mean) / normalized value
standard deviation = (14 - 13) / 1 = 1
Therefore, the standard deviation of the data set is 1.
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A researcher is interested in whether a new lotion treatment for foot odor works . she hangs out a nail salon and asks people is they have smelly feet. if they say yes, she gives them the lotion to take home, use for 3 days and return. 20 people take the lotion home . 15 return and of those 15, 10 say their feet smell good. the researchwr determines the lotion works. give 3 improvements to this experimental design (some vocabulary to consider : blocking,random assignment, placebo, double-blind , single blind etc)
Implement random assignment and a placebo control group.
Random Assignment: Implement random assignment of participants to treatment groups. Instead of relying on individuals at a nail salon who self-report having smelly feet, randomly assign participants to either the lotion treatment group or a control group. This ensures a more representative and unbiased sample, reducing potential confounding variables.
Placebo Control: Include a placebo control group in the study. In addition to the treatment group, have a group of participants who receive a placebo lotion that does not have any odor-fighting properties. This allows for a comparison between the actual lotion treatment and the placebo, helping to determine if the observed effects are due to the active ingredients or simply the placebo effect.
Double-Blind Procedure: Conduct the study using a double-blind procedure. Neither the participants nor the researcher administering the lotion should know which participants are receiving the active lotion and which are receiving the placebo. This eliminates potential biases and ensures that the results are not influenced by the participants' or researcher's expectations.
By implementing these improvements, the study design becomes more rigorous, minimizing potential biases and increasing the validity of the results.
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from a normally distributed population. Let \( \sigma \) denote the population standard deviation of Friday afternoon cab-ride times. Identify the null and alternative hypotheses.
The null and alternative hypotheses for a normally distributed population are H0: μ = μ0 and H1: μ ≠ μ0.
Let the symbol σ denote the population standard deviation of Friday afternoon cab-ride times. The null hypothesis (H0) is that the population mean is equal to a specific value, which is represented by μ0. So, the null and alternative hypotheses for a normally distributed population can be given as:
H0: μ = μ0
H1: μ ≠ μ0
The null hypothesis claims that there is no difference between the mean of the population and the hypothesized value. On the other hand, the alternative hypothesis claims that there is a difference between the mean of the population and the hypothesized value. The null and alternative hypotheses are tested using the significance level and p-value. If the p-value is less than the significance level, the null hypothesis is rejected.
In conclusion, the null and alternative hypotheses for a normally distributed population are H0: μ = μ0 and H1: μ ≠ μ0. The null hypothesis states that there is no difference between the population mean and the hypothesized value, while the alternative hypothesis claims that there is a difference between the population mean and the hypothesized value. These hypotheses are tested using the significance level and p-value.
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3. In a factory, there are three machines, Jaws,Kremp and Louy. are used to make biscuits. Machine Jaws makes 25% of the biscuits, Machine Kremp makes 45% and the rest of the bisucits are made by machine Louy. It is known that 2% of the biscuits made by Machine Jaws, 3% of the biscuit made by Machine Kremp are broken and 5% of the biscuits made by Machine L are broken.
a) Draw a tree diagram to illustrate all the possible outcomes and associated probabilities.
b) If the biscuit is selected randomly, find the probability that the biscuit is made by Machine Jaws that not broken.
c) Find the probability that the biscuit is broken.
a) Tree diagram:
Jaws (0.25)
/ \
/ \
/ \
Broken (0.02) Not Broken (0.98)
Kremp (0.45)
/ \
/ \
/ \
Broken (0.03) Not Broken (0.97)
Louy (0.30)
/ \
/ \
/ \
Broken (0.05) Not Broken (0.95)
b) The probability that a randomly selected biscuit is made by Machine Jaws and is not broken is 0.25 * 0.98 = 0.245.
c) The probability that a randomly selected biscuit is broken is calculated by summing the probabilities of the broken biscuits from each machine: (0.25 * 0.02) + (0.45 * 0.03) + (0.30 * 0.05) = 0.005 + 0.0135 + 0.015 = 0.0335.
a) The tree diagram visually represents the possible outcomes and associated probabilities for the biscuit-making process using Machines Jaws, Kremp, and Louy. The diagram is divided into three branches corresponding to each machine. The probabilities of each machine making a biscuit are indicated at the start of each branch, and the probabilities of the biscuits being broken or not broken are depicted at the end of each branch.
b) To find the probability of selecting a biscuit made by Machine Jaws that is not broken, we multiply the probability of the biscuit being made by Machine Jaws (0.25) with the probability of the biscuit not being broken given that it was made by Machine Jaws (0.98). This gives us a probability of 0.245.
c) To determine the probability of selecting a broken biscuit, we sum the probabilities of the broken biscuits from each machine. We multiply the probability of each machine making a biscuit by the probability of the biscuit being broken for that machine. Summing these values gives us a probability of 0.0335.
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use the definition of limit to find f'(x) (20 points) if f(x)=x²+x. lim fcath)-f(a) h
The derivative of f(x) is f'(x) = 2x + 1.
Given f(x) = x² + x, find f'(x) using the definition of the limit. We are given that lim fcath)-f(a) h.To calculate the derivative of f(x) using the limit definition, we use the formula: f'(x) = lim h→0 f(x + h) - f(x) / h
We first simplify the expression f(x + h) - f(x).f(x + h) = (x + h)² + (x + h)f(x) = x² + x
Subtracting the two equations, we get: f(x + h) - f(x) = x² + 2xh + h² + x + h - (x² + x)f(x + h) - f(x) = 2xh + h² + h
Next, we substitute the expressions into the formula to get:f'(x) = lim h→0 (2xh + h² + h) / h
We then factor out h from the numerator and simplify:f'(x) = lim h→0 (h(2x + h + 1)) / h
We cancel out h from the numerator and denominator, and get:f'(x) = lim h→0 (2x + h + 1) = 2x + 1
Thus, we have found the derivative of f(x) to be f'(x) = 2x + 1. We were given f(x) = x² + x and asked to find its derivative f'(x) using the definition of the limit. To do so, we first used the formula:f'(x) = lim h→0 f(x + h) - f(x) / hWe then substituted the expressions for f(x + h) and f(x) and simplified. Finally, we found the limit as h approaches 0 to be 2x + 1. Hence, the derivative of f(x) is f'(x) = 2x + 1.
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(a) 2 Big Blossom Greenhouse was commissioned to develop an extra-large rose for the Rose Parade. A random sample of blossoms from Hybrid A bushes yielded the following diameters (in inches) for mature peak blooms: 3 3 8 10 10 Use the defining formulas to find the sample variance and sample standard deviation. (b) (c) Big Blossom Greenhouse gathered another random sample of mature peak blooms from Hybrid B. The six blossoms had the following widths (in inches): 5 5 5 6 7 Find the mean, variance and standard deviation. 8 Compare the blossom diameters for Hybrid A and Hybrid B. Hybrid A: Mean = standard deviation Hybrid B: Mean = standard deviation =
The mean diameter for Hybrid A is larger than Hybrid B, indicating that, on average, Hybrid A blossoms have a larger diameter than Hybrid B blossoms.
(a) To find the sample variance and sample standard deviation for Hybrid A:
Sample diameters: 3, 3, 8, 10, 10
Step 1: Calculate the sample mean (x)
x = (3 + 3 + 8 + 10 + 10) / 5
x = 34 / 5
x = 6.8
Step 2: Calculate the deviations from the mean for each observation
Deviations: (3 - 6.8), (3 - 6.8), (8 - 6.8), (10 - 6.8), (10 - 6.8)
Deviations: -3.8, -3.8, 1.2, 3.2, 3.2
Step 3: Calculate the squared deviations for each observation
Squared deviations: (-3.8)^2, (-3.8)^2, (1.2)^2, (3.2)^2, (3.2)^2
Squared deviations: 14.44, 14.44, 1.44, 10.24, 10.24
Step 4: Calculate the sum of squared deviations
Sum of squared deviations: 14.44 + 14.44 + 1.44 + 10.24 + 10.24
Sum of squared deviations: 50.8
Step 5: Calculate the sample variance (s^2)
s^2 = Sum of squared deviations / (n - 1)
s^2 = 50.8 / (5 - 1)
s^2 = 50.8 / 4
s^2 = 12.7
Step 6: Calculate the sample standard deviation (s)
s = sqrt(s^2)
s = sqrt(12.7)
s ≈ 3.57
Therefore, the sample variance for Hybrid A is approximately 12.7 and the sample standard deviation is approximately 3.57.
(b) For Hybrid B:
Sample widths: 5, 5, 5, 6, 7
Step 1: Calculate the sample mean (x)
x = (5 + 5 + 5 + 6 + 7) / 5
x = 28 / 5
x = 5.6
Step 2: Calculate the deviations from the mean for each observation
Deviations: (5 - 5.6), (5 - 5.6), (5 - 5.6), (6 - 5.6), (7 - 5.6)
Deviations: -0.6, -0.6, -0.6, 0.4, 1.4
Step 3: Calculate the squared deviations for each observation
Squared deviations: (-0.6)^2, (-0.6)^2, (-0.6)^2, (0.4)^2, (1.4)^2
Squared deviations: 0.36, 0.36, 0.36, 0.16, 1.96
Step 4: Calculate the sum of squared deviations
Sum of squared deviations: 0.36 + 0.36 + 0.36 + 0.16 + 1.96
Sum of squared deviations: 3.2
Step 5: Calculate the sample variance (s^2)
s^2 = Sum of squared deviations / (n - 1)
s^2 = 3.2 / (5 - 1)
s^2 = 3.2 / 4
s^2 = 0.8
Step 6: Calculate the sample standard deviation (s)
s = sqrt(s^2)
s = sqrt(0.8)
s ≈ 0.89
The mean for Hybrid B is 5.6, the variance is approximately 0.8, and the standard deviation is approximately 0.89.
(c) To compare the blossom diameters for Hybrid A and Hybrid B:
Hybrid A: Mean = 6.8, Standard deviation = 3.57
Hybrid B: Mean = 5.6, Standard deviation = 0.89
We can observe that the mean diameter for Hybrid A is larger than Hybrid B, indicating that, on average, Hybrid A blossoms have a larger diameter than Hybrid B blossoms. Additionally, the standard deviation for Hybrid A is larger than Hybrid B, indicating greater variability in the diameter of Hybrid A blossoms compared to Hybrid B blossoms.
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Either use Section 16.2 methods OR use Green's Theorem to evaluate the line integral § −2y³ dx + 2x' dy where C is the circle with equation x² + y² = 4 [assume that C rotates counterclockwise] 9. (10pts) Either use Section 16.2 methods OR use Green's Theorem to evaluate the line integral § −2y³ dx + 2x' dy where C is the circle with equation x² + y² = 4 [assume that C rotates counterclockwise]
Previous question
The value of the line integral is zero.To evaluate the line integral using Green's Theorem, we need to express the line integral as a double integral over the region enclosed by the curve C.
Green's Theorem states:
∮C P dx + Q dy = ∬R ( ∂Q/∂x - ∂P/∂y ) dA
Here, P and Q are the components of the vector field F(x, y) = (P, Q), and R is the region enclosed by the curve C.
In this case, the line integral is given as:
∮C (-2y³ dx + 2x dy)
We can rewrite this in terms of P and Q:
P = 2x
Q = -2y³
Now, let's calculate the partial derivatives:
∂Q/∂x = ∂/∂x (-2y³) = 0
∂P/∂y = ∂/∂y (2x) = 0
Since both partial derivatives are zero, the expression ∂Q/∂x - ∂P/∂y is also zero. Therefore, the line integral simplifies to:
∮C (-2y³ dx + 2x dy) = ∬R 0 dA
The double integral of zero over any region is simply zero. Therefore, the value of the line integral is zero.
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Let T be the linear transformation on R³ defined by T(x, y, z) = (4x+2, 2x + 3y + 2z, x + 4z). Find the eigenvalues and eigenvectors of T and diagonalize T. Problem 175 Let M2x2 (R) be the vector space of all real 2 x 2 matrices and let T be the linear transformation on M2x2 (R) defined by 2x2(e) T [a+b+d a+b+c] b+c+d a+c+d = Find the eigenvalues and eigenvectors of T and diagonalize T. 45
For the linear transformation T on R³, the eigenvalues are 4, 3, and 2 with corresponding eigenvectors. For the transformation T on M₂x₂(R), the eigenvalues are 1, 0, and -1 with respective eigenvectors. Both T can be diagonalized.
For the linear transformation T: R³ -> R³, the characteristic equation is det(A - λI) = 0, where A is the matrix representation of T and λ is an eigenvalue. By solving this equation, we find the eigenvalues λ₁ = 4, λ₂ = 3, and λ₃ = 2. To find the eigenvectors, we substitute each eigenvalue into the equation (A - λI)v = 0 and solve for v. The eigenvectors are v₁ = (1, -1, 1), v₂ = (-1, 1, 0), and v₃ = (-2, 0, 1). To diagonalize T, we form the matrix P using the eigenvectors as columns, and the diagonal matrix D with the eigenvalues as diagonal entries. The diagonalization is given by T = PDP⁻¹.
For the linear transformation T: M₂x₂(R) -> M₂x₂(R), the characteristic equation is det(A - λI) = 0, where A is the matrix representation of T and λ is an eigenvalue. By solving this equation, we find the eigenvalues λ₁ = 1, λ₂ = 0, and λ₃ = -1. To find the eigenvectors, we substitute each eigenvalue into the equation (A - λI)v = 0 and solve for v. The eigenvectors are v₁ = [1 0; 0 0], v₂ = [0 1; 1 0], and v₃ = [1 0; 0 -1]. To diagonalize T, we form the matrix P using the eigenvectors as columns, and the diagonal matrix D with the eigenvalues as diagonal entries. The diagonalization is given by T = PDP⁻¹.
For the linear transformation T on R³, the eigenvalues are 4, 3, and 2 with corresponding eigenvectors. For the transformation T on M₂x₂(R), the eigenvalues are 1, 0, and -1 with respective eigenvectors. Both T can be diagonalized.
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The amount of time to complete a physical activity in a PE class is approximately normally normally distributed with a mean of 35.1 seconds and a standard deviation of 6.8 seconds. a) What is the probability that a randomly chosen student completes the activity in less than 31.1 seconds? b) What is the probability that a randomly chosen student completes the activity in more than 42.8 seconds'? complete the activity? d) 75% of all students finish the activity in less than seconds.
a) The probability that a randomly chosen student completes the activity in less than 31.1 seconds is approximately 0.2787.
b) the probability that a randomly chosen student completes the activity in more than 42.8 seconds is approximately 0.1289.
c) We can find the probability that a randomly chosen student completes the activity in between any two given values.
d) 75% of all students finish the activity in less than approximately 39.62 seconds.
a) To find the probability that a randomly chosen student completes the activity in less than 31.1 seconds, we need to standardize the value using the formula:
z = (x - mu) / sigma
where x is the time taken by the student, mu is the mean time, and sigma is the standard deviation.
So, we have:
z = (31.1 - 35.1) / 6.8 = -0.5882
From the normal distribution table or calculator, we can find that the probability of a standard normal variable being less than -0.5882 is 0.2787. Therefore, the probability that a randomly chosen student completes the activity in less than 31.1 seconds is approximately 0.2787.
b) To find the probability that a randomly chosen student completes the activity in more than 42.8 seconds, we again need to standardize the value:
z = (42.8 - 35.1) / 6.8 = 1.1324
From the normal distribution table or calculator, we can find that the probability of a standard normal variable being more than 1.1324 is 0.1289. Therefore, the probability that a randomly chosen student completes the activity in more than 42.8 seconds is approximately 0.1289.
c) To find the probability that a randomly chosen student takes between two values, say a and b seconds, we need to standardize both values and then find the area under the standard normal curve between those values. Mathematically, this can be written as:
P(a < x < b) = P[(a - mu) / sigma < z < (b - mu) / sigma]
Using this formula, we can find the probability that a randomly chosen student completes the activity in between any two given values.
d) If 75% of all students finish the activity in less than some time t, then we can find this value of t by standardizing it and using the standard normal distribution table or calculator to find the corresponding z-score.
Let z be the z-score for the given percentile (75%). Then we have:
z = invNorm(0.75) ≈ 0.6745
Using the formula for standardization, we have:
z = (t - mu) / sigma
Substituting the values of mu and sigma from the given information, we get:
0.6745 = (t - 35.1) / 6.8
Solving for t gives:
t = 0.6745 * 6.8 + 35.1 ≈ 39.62
Therefore, 75% of all students finish the activity in less than approximately 39.62 seconds.
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: Evaluate -X lim x→[infinity] ex + e-x
The value of -X lim x→∞ ex + e−x is -∞. This is because as x approaches infinity, the exponential functions ex and e−x both approach infinity, but in opposite directions. Therefore, the sum of the two functions approaches infinity in the negative direction.
The exponential function ex is defined as e^x = 1 + x + x^2/2 + x^3/3 + ..., where x is any real number. As x approaches infinity, the terms in the series become increasingly large, so the value of ex approaches infinity. The same is true for the exponential function e−x. However, since e−x is the negative of e^x, it approaches infinity in the negative direction.
When we multiply ex and e−x, we get e^2x, which also approaches infinity. However, since x is approaching infinity, the value of e^2x is approaching infinity much more slowly than the value of ex or e−x. Therefore, the sum of ex and e−x approaches infinity in the negative direction.
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Find all the second partial derivatives. f(x,y)=x 7
y 6
+5x 7
y f xx
(x,y)= f xy
(x,y)= f yx
(x,y)= f yy
(x,y)=
The second partial derivatives of f(x,y) are
[tex]f_{xx}(x,y) = 42x^5 y^6 + 210x^5 y \\ f_{xy}(x,y) = 42x^5 y^5 + 35x^6 \\ f_{yx}(x,y) = 42x^5 y^5 + 35x^6 \\ f_{yy}(x,y) = 30x^7 y^4[/tex]
Partial derivatives explainedGiven the function;
[tex]f(x,y) = x^7 y^6 + 5x^7 y[/tex]
Take partial derivatives with respect to x:
[tex]f_x(x,y) = 7x^6 y^6 + 35x^6 y \\ f_xx(x,y) = 42x^5 y^6 + 210x^5 y[/tex]
Take partial derivative with respect to y
[tex]f_y(x,y) = 6x^7 y^5 + 5x^7 \\ f_xy(x,y) = 42x^5 y^5 + 35x^6[/tex]
Take the partial derivative of f_x with respect to y and the partial derivative of f_y with respect to x:
[tex]f_{xy}(x,y) = 42x^5 y^5 + 35x^6 \\ f_{yx}(x,y) = 42x^5 y^5 + 35x^6[/tex]
Therefore, the mixed partial derivatives are equal.
Taking the second partial derivative with respect to y
[tex]f_{yy}(x,y) = 30x^7 y^4[/tex]
Therefore, the second partial derivatives of f(x,y) are:
[tex]f_{xx}(x,y) = 42x^5 y^6 + 210x^5 y \\ f_{xy}(x,y) = 42x^5 y^5 + 35x^6 \\ f_{yx}(x,y) = 42x^5 y^5 + 35x^6 \\ f_{yy}(x,y) = 30x^7 y^4[/tex]
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Please help on this, I'm not sure if I'm correct (ignore what I wrote before, like I said before I'm not sure if it's correct)
A table and graph for the specific coordinates (r, θ) is shown below.
How to develop a table that models the specific polar coordinates?In Geometry, the relationship between a polar coordinate (r, θ) and a rectangular coordinate (x, y) based on the conversion rules is given by the following polar equations:
a = rcos(θ) ....equation 1.
b = rsin(θ) ....equation 2.
Where:
θ is the angle.r is the radius of a circle.Based on the information provided, the cardioid microphone can be modeled by the following polar equation:
r = 3 + 3cos(θ)
When θ = 0, the value of r is given by:
r = 3 + 3cos(0)
r = 3 + 3 = 6.
When θ = 45, the value of r is given by:
r = 3 + 3cos(45)
r = 3 + 2.1 = 5.1.
When θ = 90, the value of r is given by:
r = 3 + 3cos(90)
r = 3 + 0 = 3.
When θ = 135, the value of r is given by:
r = 3 + 3cos(135)
r = 3 - 0.71 = 2.29.
When θ = 180, the value of r is given by:
r = 3 + 3cos(180)
r = 3 - 1 = 2.
When θ = 225, the value of r is given by:
r = 3 + 3cos(225)
r = 3 - 0.71 = 2.29.
When θ = 270, the value of r is given by:
r = 3 + 3cos(270)
r = 3 + 0 = 3.
When θ = 315, the value of r is given by:
r = 3 + 3cos(315)
r = 3 + 2.1 = 5.1.
When θ = 2π, the value of r is given by:
r = 3 + 3cos(2π) = 3 + 3cos(360)
r = 3 + 3 = 6.
Therefore, a table for the specific polar coordinate (r, θ) should be completed as follows;
θ r
0 6
45 5.1
90 3
135 2.29
180 2
225 2.29
270 3
315 5.1
2π 6
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In 2021, we expect that almost every American adult has a smart phone. However, things were different in 2011: According to a Pew Research Center study, in May 2011, 34\% of all American adults had a smart phone (one which the user can use to read email and surf the Internet). A communications professor at Perimeter College (now a part of Georgia State University) believed this percentage to be higher among community college students. She selects 339 community college students at random and finds that 136 of them have a smart phone. In testing the hypotheses: H0:p=0.34 versus Ha:p>0.34, she calculates the test statistic as z=2.3779. Find the p □ value that coordinates with this test statistic. \{Important: Round your final answer to 5 decimal places\} our Answer:
We take the area in the right tail of the standard normal distribution. Therefore, the p-value is:p-value = 1 - 0.00831376 = 0.99168624.
We are told that a communications professor at Perimeter College believed this percentage to be higher among community college students. She selects 339 community college students at random and finds that 136 of them have a smartphone.The null and alternative hypotheses are: H0:p=0.34, the proportion of American adults with a smartphone.Ha:p>0.34, the proportion of American adults with a smartphone is greater than 0.34.The given test statistic is z=2.3779. We have to find the p-value that coordinates with this test statistic.We know that the p-value is the probability of obtaining a test statistic at least as extreme as the one observed, assuming the null hypothesis is true.To find the p-value, we use the normal distribution table. The z-value is 2.3779 and the corresponding probability is 0.00831376. However, since the alternative hypothesis is a greater than alternative, we take the area in the right tail of the standard normal distribution.
Therefore, the p-value is: p-value = 1 - 0.00831376 = 0.99168624.Explanation:Given that a communications professor at Perimeter College believed this percentage to be higher among community college students. She selects 339 community college students at random and finds that 136 of them have a smartphone. The null and alternative hypotheses H0:p=0.34, the proportion of American adults with a smartphone. Ha:p>0.34, the proportion of American adults with a smartphone is greater than 0.34.The given test statistic is z=2.3779. We have to find the p-value that coordinates with this test statistic. The p-value is the probability of obtaining a test statistic at least as extreme as the one observed, assuming the null hypothesis is true.To find the p-value, we use the normal distribution table. The z-value is 2.3779 and the corresponding probability is 0.00831376. However, since the alternative hypothesis is a greater than alternative, we take the area in the right tail of the standard normal distribution. Therefore, the p-value is:p-value = 1 - 0.00831376 = 0.99168624.
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Suppose that the times taken for germination for cauliflower seeds are normally distributed with a mean of
7.1
days. Suppose also that exactly
90%
of the cauliflower seeds germinate in
6.2
days or more. Find the standard deviation of times taken for germination for cauliflower seeds. Carry your intermediate computations to at least four decimal places. Round your answer to at least two decimal places.
The standard deviation of times taken for germination for cauliflower seeds is approximately 0.70 days.
To find the standard deviation of times taken for germination for cauliflower seeds, we can use the concept of the standard normal distribution.
Let's denote the standard deviation as σ.
Given that 90% of the cauliflower seeds germinate in 6.2 days or more, we can find the z-score corresponding to this percentile.
The z-score can be calculated using the formula:
z = (x - μ) / σ
where:
x = 6.2 (the value of interest)
μ = 7.1 (mean)
σ = standard deviation (to be determined)
To find the z-score, we can rearrange the formula as follows:
σ = (x - μ) / z
Substituting the given values:
σ = (6.2 - 7.1) / z
To find the z-score corresponding to the 90th percentile, we look up the value in the standard normal distribution table or use a calculator. The z-score for a cumulative probability of 0.9 is approximately 1.2816.
Substituting the z-score into the formula:
σ = (6.2 - 7.1) / 1.2816
Performing the calculation:
σ = -0.9 / 1.2816 ≈ -0.7020
Rounding the standard deviation to two decimal places, we get:
σ ≈ -0.70
Therefore, the standard deviation of times taken for germination for cauliflower seeds is approximately 0.70 days.
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Mean μ = 7.1 daysProbability P(X ≥ 6.2) = 0.90We are supposed to find the standard deviation of times taken for germination for cauliflower seeds.Since the probability distribution of the germination times is normal, it follows a standard normal distribution, that is, Z-distribution.
Therefore, we can transform the given data into the standard normal distribution as follows;Z = (X - μ) / σWhereX = 6.2 daysσ = standard deviationThe given probability can be rewritten as:P(X ≥ 6.2) = P(Z ≥ (6.2 - 7.1) / σ)P(Z ≥ -0.9 / σ) = 0.90Now, we need to find the Z value corresponding to the given probability using a standard normal distribution table.Using the table, we can find the Z value as;Z = 1.28Thus, substituting Z = 1.28 and solving for σ, we get;1.28 = -0.9 / σσ = -0.9 / 1.28σ = 0.7031Approximating to two decimal places, the standard deviation is given by;σ = 0.70Therefore, the standard deviation of times taken for germination for cauliflower seeds is 0.70 days.
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A gum manufacturer claims that on average the flavor of an entire packet of its gum would last for more than 39 minutes. A quality controller selects a random sample of 55 packets of gum. She finds the average time for which the gum flavor lasts is 40 minutes with a standard deviation of 5.67 minutes.
a) Formulate a hypothesis test to validate the manufacturer's claim.
b) After a new technique to improve the lasting period of gum flavor was applied, the quality controller reselects 60 packets of gum and found out that the average time for which the gum flavor lasts is 45 minutes with a standard deviation of 3.15 minutes. Is there sufficient evidence to conclude that the new technique significantly increased the lasting time?
c) Use a 95% confidence interval for the population average time for which the flavor lasts to validate the manufacturer's claim after the new technique is applied.
(a) A one-sample t-test was used to test a gum manufacturer's claim that the mean flavor time of a packet of gum is more than 39 minutes, and there was sufficient evidence to support the claim.
b) After a new technique was applied, a one-sample t-test was used to test whether the mean flavor time of a packet of gum is significantly higher than 39 minutes, and there was sufficient evidence to support the claim that the new technique increased the lasting time of the gum flavor.
c) A 95% confidence interval was calculated to validate the new population average time for which the flavor lasts after the new technique was applied, and the interval did not include 39 minutes, confirming the effectiveness of the new technique.
a) To test the manufacturer's claim, we can set up a hypothesis test,
Null hypothesis (H0): The mean flavor time of the 55 packets of gum is equal to 39 minutes.
Alternative hypothesis (Ha): The mean flavor time of the 55 packets of gum is greater than 39 minutes.
We can use a one-sample t-test to compare the mean flavor time of the sample to the manufacturer's claim.
The test statistic is calculated as:
t = (X - μ) / (s / √n)
where X is the sample mean,
μ is the population mean (in this case, 39 minutes),
s is the sample standard deviation,
And n is the sample size (55).
Using the information given in the problem,
We can calculate the test statistic as,
t = (40 - 39) / (5.67 / √55)
= 2.62
We can find the p-value associated with this test statistic using a t-distribution table.
For a one-tailed test with 54 degrees of freedom (55 - 1), the p-value is less than 0.01.
Since the p-value is less than the significance level of 0.05,
We reject the null hypothesis and conclude that there is sufficient evidence to support the claim that the mean flavor time of the 55 packets of gum is greater than 39 minutes.
b) To test whether the new technique significantly increased the lasting time, we can set up a hypothesis test:
Null hypothesis (H0): The mean flavor time of the 60 packets of gum is equal to 39 minutes.
Alternative hypothesis (Ha): The mean flavor time of the 60 packets of gum is greater than 39 minutes.
We can use a one-sample t-test again to compare the mean flavor time of the sample to the manufacturer's claim.
The test statistic is calculated as,
t = (X - μ) / (s / √n)
where X is the sample mean,
μ is the population mean (in this case, 39 minutes),
s is the sample standard deviation,
And n is the sample size (60).
Using the information given in the problem, we can calculate the test statistic as:
t = (45 - 39) / (3.15 / √60)
= 11.55
We can find the p-value associated with this test statistic using a t-distribution table.
For a one-tailed test with 59 degrees of freedom (60 - 1), the p-value is less than 0.00001.
Since the p-value is less than the significance level of 0.05, we reject the null hypothesis and conclude that there is sufficient evidence to support the claim that the new technique significantly increased the lasting time of the gum flavor.
(c) We can use the following formula to calculate the 95% confidence interval for the mean flavor time:
⇒ X± tα/2(s / √n)
where X is the sample mean (45 minutes),
s is the sample standard deviation (3.15 minutes),
n is the sample size (60),
And tα/2 is the t-value from the t-distribution with 59 degrees of freedom (corresponding to a 95% confidence level).
Using a t-distribution table,
we can find that t0.025,59 = 2.0027.
Plugging in the values, we get,
45 ± 2.0027(3.15 / √60)
This simplifies to,
(42.61, 47.39)
Therefore, we are 95% confident that the true population average time for which the flavor lasts after the new technique is applied is between 42.61 and 47.39 minutes.
Since this confidence interval does not include the manufacturer's claim of 39 minutes, we can conclude that the new technique did indeed significantly increase the lasting time of the gum flavor.
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The volume of a rectangular prism is (x³-3x² + 5x-3), and the area of its base is (x²-2). If the volume of a rectangu
prism is the product of its base area and height, what is the height of the prism?
O x-3+
7x-9
x²-2
7x-9
x²-3x²+5x-3
O x-3+-
O x-3+7X+22
7x+3
x²-3x²+5x-3
O x-3+-
The height of the rectangular prism is (x³ - 3x² + 5x - 3) / (x² - 2).
To find the height of the rectangular prism, we need to divide the volume of the prism by the area of its base.
Given:
Volume of the prism = x³ - 3x² + 5x - 3
Area of the base = x² - 2
To find the height, we divide the volume by the area:
Height = Volume / Area
Height = (x³ - 3x² + 5x - 3) / (x² - 2)
Therefore, the height of the rectangular prism is (x³ - 3x² + 5x - 3) / (x² - 2).
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