The 90% confidence interval is: (2.51, 3.22)
Confidence interval :It is a boundary of values which is eventually to comprise a population value with a certain degree of confidence. It is usually shown as a percentage whereby a population means lies within the upper and lower limit of the provided confidence interval.
We have the following information :
Number of students randomly selected, n = 15.Sample mean, x(bar) = 2.86Sample standard deviation, s = 0.78Degree of confidence, c = 90% or 0.90The level of significance is calculated as:
[tex]\alpha =1-c\\\\\alpha =1-0.90\\\\\alpha =0.10[/tex]
The degrees of freedom for the case is:
df = n - 1
df = 15 - 1
df = 14
The 90% confidence interval is calculated as:
=x(bar) ±[tex]t_\frac{\alpha }{2}[/tex], df [tex]\frac{s}{\sqrt{n} }[/tex]
= 2.86 ±[tex]t_\frac{0.10 }{2}[/tex], 14 [tex]\frac{0.78}{\sqrt{15} }[/tex]
= 2.86 ± 1.761 × [tex]\frac{0.78}{\sqrt{15} }[/tex]
= 2.86 ± 0.3547
= (2.51, 3.22)
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What does it mean when A is confounded with BC? a) A is contributed to the result b) BC is contributed to the result c) The computed coefficients are related to the sum of the two individual effects.
When A is confounded with BC, it means that the computed coefficients are related to the sum of the two individual effects.
Confounding happens when two variables are related to the result in such a way that it is not possible to distinguish the effects of the two variables on the outcome. This is commonly known as the confounding effect. In experimental designs, it is important to identify the confounding variables, as they can lead to biased or inaccurate results.
This can also impact the interpretation of the results. Confounding is particularly problematic when the confounding variable is related to the outcome and the exposure variable. If the confounding variable is not measured, it can lead to erroneous conclusions. Therefore, it is important to identify and control for confounding variables to obtain accurate results.
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I need these high school statistics questions to be
solved
33. In 2009, DuPont Automotive reported that 18% of cars in North America were white in color. We are interested in the proportion of white cars in a random sample of 400 cars. Find the z-score that r
The z-score for the proportion of white cars in a random sample of 400 cars is 0, indicating that the observed proportion is equal to the population proportion.
To compute the z-score for the proportion of white cars in a random sample of 400 cars, we need to use the formula for calculating the z-score:
z = (p - P) / sqrt(P * (1 - P) / n)
Where:
p is the observed proportion (18% or 0.18)
P is the population proportion (18% or 0.18)
n is the sample size (400)
Calculating the z-score:
z = (0.18 - 0.18) / sqrt(0.18 * (1 - 0.18) / 400)
z = 0 / sqrt(0.18 * 0.82 / 400)
z = 0 / sqrt(0.1476 / 400)
z = 0 / sqrt(0.000369)
z = 0
Therefore, the z-score for the proportion of white cars in a random sample of 400 cars is 0.
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If y=7 is a horizontal asymptote of a rational function f, then which of the following must be true? a) lim x->7 f(x)=[infinity] b) lim x->[infinity] f(x)=7 c) lim x->0 f(x)=7 d) lim x->7 f(x)=0 e) lim x->-[infinity] f(x)=-7
If y = 7 is a horizontal asymptote of a rational function f, then which of the following must be true?If y = 7 is a horizontal asymptote of a rational function f, then the option that must be true is b) limx→∞f(x) = 7.
A horizontal asymptote is a horizontal line on the graph of a function that the curve approaches as x approaches positive or negative infinity.The limit of the function as x approaches infinity is equal to the value of the horizontal asymptote. If y = k is the horizontal asymptote of f(x), we can write this as follows:lim x→±∞f(x) = kLet y = 7 be a horizontal asymptote of a rational function f.
As x becomes increasingly large in the positive or negative direction, the limit of the function approaches 7. Therefore, limx→∞f(x) = 7. So, option b) is the right answer.
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if f, g, h are the midpoints of the sides of triangle cde. find the following lengths.
FG = ____
GH = ____
FH = ____
Given: F, G, H are the midpoints of the sides of triangle CDE.
The values can be tabulated as follows:|
FG | GH | FH |
9 | 10 | 8 |
To Find:
Length of FG, GH and FH.
As F, G, H are the midpoints of the sides of triangle CDE,
Therefore, FG = 1/2 * CD
Now, let's calculate the length of CD.
Using the mid-point formula for line segment CD, we get:
CD = 2 GH
CD = 2*9
CD = 18
Therefore, FG = 1/2 * CD
Calculating
FGFG = 1/2 * CD
CD = 18FG = 1/2 * 18
FG = 9
Therefore, FG = 9
Similarly, we can calculate GH and FH.
Using the mid-point formula for line segment DE, we get:
DE = 2FH
DE = 2*10
DE = 20
Therefore, GH = 1/2 * DE
Calculating GH
GH = 1/2 * DE
GH = 1/2 * 20
GH = 10
Therefore, GH = 10
Now, using the mid-point formula for line segment CE, we get:
CE = 2FH
FH = 1/2 * CE
Calculating FH
FH = 1/2 * CE
FH = 1/2 * 16
FH = 8
Therefore, FH = 8
Hence, the length of FG is 9, length of GH is 10 and length of FH is 8.
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prove that difference of square of two distinct odd number is always multiple of 8
The difference of the squares of two distinct odd numbers is always a multiple of 8.
Let's assume we have two distinct odd numbers, represented as (2k + 1) and (2m + 1), where k and m are integers.
The square of the first odd number, (2k + 1)², can be expanded as:
(2k + 1)² = 4k² + 4k + 1
The square of the second odd number, (2m + 1)², can be expanded as:
(2m + 1)² = 4m² + 4m + 1
Now, let's find the difference between the two squares:
(2k + 1)² - (2m + 1)² = (4k² + 4k + 1) - (4m² + 4m + 1)
= 4k² + 4k + 1 - 4m² - 4m - 1
= 4(k² - m²) + 4(k - m)
= 4(k - m)(k + m) + 4(k - m)
We can see that the expression 4(k - m)(k + m) + 4(k - m) is divisible by 4 because it contains a factor of 4. However, to prove that it is always a multiple of 8, we need to show that it is also divisible by another factor of 2.
For that, we can notice that both (k - m) and (k + m) are even, as the sum or difference of two odd numbers is always even. Therefore, the entire expression 4(k - m)(k + m) + 4(k - m) is divisible by 2.
Since the expression is divisible by both 4 and 2, it is a multiple of 8
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what is the confidence level for the interval x ± 1.43⁄ n ? (round your answer to one decimal place.)
The formula for a confidence interval is point estimate ± margin of error. Where point estimate is the sample mean, and the margin of error is calculated as z * (standard deviation / square root of sample size) or t * (standard deviation / square root of sample size) based on whether the population standard deviation is known or unknown.
The formula for a confidence interval is point estimate ± margin of error. Where point estimate is the sample mean, and the margin of error is calculated as z * (standard deviation / square root of sample size) or t * (standard deviation / square root of sample size) based on whether the population standard deviation is known or unknown. The confidence level is the probability that the true population mean lies within the confidence interval.
A confidence interval can be expressed as x ± E, where E is the margin of error. The formula for the margin of error is E = z* (s/√n), where z is the critical value from the standard normal distribution corresponding to the desired confidence level, s is the sample standard deviation, and n is the sample size.The confidence level for the interval x ± 1.43/ n is not specified in the problem, which means that we cannot determine it. If the confidence level is not given, it is impossible to determine it based on the interval alone. Therefore, we cannot round the answer as it is not possible to calculate it. We would need more information to do so.
Answer: The confidence level for the interval x ± 1.43⁄ n cannot be determined without additional information.
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An employee worked for 8 hours on 2 days, 6 hours on 1 day, and 4 hours on 2 days. What is the average number of hours the employee worked per day?
a. 4 hours.
b. 5 hours.
c. 6 hours.
d. 7 hours.
The average number of hours worked per day is 30 ÷ 5 = 6 hours. Therefore, the correct option is c. 6 hours.
To calculate the average number of hours the employee worked per day, we need to add up all the hours and divide it by the total number of days worked.
We are given that an employee worked for 8 hours on 2 days, 6 hours on 1 day, and 4 hours on 2 days.
So, the total hours worked by the employee is 8 x 2 + 6 x 1 + 4 x 2 = 16 + 6 + 8 = 30 hours.
The employee worked on a total of 5 days.
Therefore, the average number of hours worked per day is 30 ÷ 5 = 6 hours.
Therefore, the correct option is c. 6 hours.
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Jenna owes the bank $2,300 which accumulates interest at 6% compounded quarterly
from April 1, 2016, to January 1, 2019,. After January 1, 2019, the debt is compounded semi- annually at a rate of 10%. What is the accumulated value of the debt owed January 1, 2021?
Which of the following statements is not true about chi-square distributions? The mean decreases as the degrees of freedom increase. OPG? < 0) = 0 O PU2 > 3) is larger for a chi-square distribution with df = 10 than for df = 1 There are an infinite number of chi-square distributions, depending on degrees of freedom. They are always skewed to the right Previous Only saved at 4:44pm
The statement "The mean decreases as the degrees of freedom increase" is not true about chi-square distributions.
Is it true that the mean of a chi-square distribution decreases as the degrees of freedom increase?In fact, the mean of a chi-square distribution is equal to its degrees of freedom. It does not decrease as the degrees of freedom increase.
The mean remains constant regardless of the degrees of freedom. This is an important characteristic of chi-square distributions.
Regarding the other statements:
The statement "OPG? < 0) = 0" is true. The probability of a chi-square random variable being less than zero is always zero, as chi-square values are non-negative.The statement "OPU2 > 3) is larger for a chi-square distribution with df = 10 than for df = 1" is true. As the degrees of freedom increase, the right-tail probability of a chi-square distribution also increases.The statement "There are an infinite number of chi-square distributions, depending on degrees of freedom" is true. The number of chi-square distributions is infinite because the degrees of freedom can take any positive integer value.The statement "They are always skewed to the right" is generally true. Chi-square distributions tend to be skewed to the right, especially when the degrees of freedom are small.In summary, the statement that is not true about chi-square distributions is that the mean decreases as the degrees of freedom increase.
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Construct a data set that has the given statistics. n = 7 X = 9 S = 0 What does the value n mean? OA. The number of values in the sample data set. OB. The mean of the sample data set. OC. The differen
The value n in this context refers to the number of values in the sample data set.
In this case, the data set has n=7, which means there are 7 values in the sample.
The value X=9 represents the mean or average of the sample data set, while S=0 represents the standard deviation of the sample.
To construct a data set with these statistics, we can use the formula for calculating the standard deviation:
S = sqrt [ Σ ( Xi - X )2 / ( n - 1 ) ]
where Xi represents each value in the data set and X represents the mean of the data set.
Since S=0, we know that each value in the data set must be equal to the mean, which is X=9. Therefore, a possible data set that satisfies these statistics is:
{9, 9, 9, 9, 9, 9, 9}
In this data set, there are n=7 values, and each value is equal to X=9. The standard deviation is calculated as:
S = sqrt [ (0 + 0 + 0 + 0 + 0 + 0 + 0) / (7 - 1) ] = 0
which confirms that S=0 for this data set.
Overall, the value n represents the number of values in a sample data set.
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Since the early 13th century, coins struck by the Royal Mint in
England have been evaluated for their metal content on a sample
basis, in a ceremony called the Trial of the Pyx. This ceremony
does not
It's a ceremony that tests random samples of coins for their metal content. The Trial of the Pyx's significance can be traced back to medieval times when the Royal Mint produced the coins manually.
The Trial of the Pyx is a ceremony where coins that are struck by the Royal Mint in England have been evaluated for their metal content on a sample basis since the early 13th century. It is not a ceremony that evaluates the content of coins one by one.
What is the Trial of the Pyx?
The Trial of the Pyx is a public test carried out by the Royal Mint in England to ensure the standards of its coin production are being adhered to. The Trial of the Pyx ceremony has been carried out every year since 1282, making it one of the oldest and most traditional events in the country.The ceremony is done to test the coins' accuracy in relation to their weight and metal content. It is not a ceremony that evaluates the content of coins one by one.
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11.)
12.)
Find the indicated z score. The graph depicts the standard normal distribution with mean 0 and standard deviation 1. The indicated z score is (Round to two decimal places as needed.) A 0.2514, Z 0
Fi
Given the standard normal distribution with a mean of 0 and standard deviation of 1. We are to find the indicated z-score. The indicated z-score is A = 0.2514.
We know that the standard normal distribution has a mean of 0 and standard deviation of 1, therefore the probability of z-score being less than 0 is 0.5. If the z-score is greater than 0 then the probability is greater than 0.5.Hence, we have: P(Z < 0) = 0.5; P(Z > 0) = 1 - P(Z < 0) = 1 - 0.5 = 0.5 (since the normal distribution is symmetrical)The standard normal distribution table gives the probability that Z is less than or equal to z-score. We also know that the normal distribution is symmetrical and can be represented as follows.
Since the area under the standard normal curve is equal to 1 and the curve is symmetrical, the total area of the left tail and right tail is equal to 0.5 each, respectively, so it follows that:Z = 0.2514 is in the right tail of the standard normal distribution, which means that P(Z > 0.2514) = 0.5 - P(Z < 0.2514) = 0.5 - 0.0987 = 0.4013. Answer: Z = 0.2514, the corresponding area is 0.4013.
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4. What is the SSE in the following ANOVA table? [2pts] Sum of squares d.f. 5 Treatments Error 84 Mean squares 10 F-statistic 3.24
The SSE in the following ANOVA table is 84.
In the given ANOVA table, the value of SSE can be found under the column named Error.
The value of SSE is 84.
The ANOVA table represents the analysis of variance, which is a statistical method that is used to determine the variance that is present between two or more sample means.
The ANOVA table contains different sources of variation that are calculated in order to determine the overall variance.
Summary: The SSE in the ANOVA table provided is 84. The ANOVA table contains different sources of variation that are calculated in order to determine the overall variance.
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Find a power series representation for the function. (Center your power series representation at x=0.) f(x)=5+x1f(x)=∑n=0[infinity]( Determine the interval of convergence. (Enter your answer using interval notation.)
To find a power series representation for the function [tex]\(f(x) = 5 + x\),[/tex] we can start by expanding the function using the binomial series.
Using the binomial series expansion, we have:
[tex]\[f(x) = 5 + x = 5 + \sum_{n=0}^{\infty} \binom{1}{n} x^n\][/tex]
Since the binomial coefficient [tex]\(\binom{1}{n}\)[/tex] simplifies to 1 for all [tex]\(n\),[/tex] we can rewrite the series as:
[tex]\[f(x) = 5 + \sum_{n=0}^{\infty} x^n\][/tex]
The series [tex]\(\sum_{n=0}^{\infty} x^n\)[/tex] is a geometric series with a common ratio of [tex]\(x\)[/tex]. The formula for the sum of an infinite geometric series is:
[tex]\[S = \frac{a}{1 - r}\][/tex]
where [tex]\(a\)[/tex] is the first term and [tex]\(r\)[/tex] is the common ratio. In this case, [tex]\(a = 1\)[/tex] and [tex]\(r = x\).[/tex]
Thus, we have:
[tex]\[f(x) = 5 + \frac{1}{1 - x}\][/tex]
Therefore, the power series representation for the function [tex]\(f(x) = 5 + x\) is \(f(x) = 5 + \sum_{n=0}^{\infty} x^n\)[/tex] and its interval of convergence is [tex]\((-1, 1)\) (excluding the endpoints).[/tex]
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TV advertising agencies face increasing challenges in reaching audience members because viewing TV programs via digital streaming is gaining in popularity. A poll reported that 55% of 2341 American adults surveyed said they have watched digitally streamed TV programming on some type of device.
What sample size would be required for the width og 99%CI to be at most 0.06 irrespective of the value of (beta)?
In order to find the sample size required for the width of a 99%CI to be at most 0.06 irrespective of the value of (beta), we can use the given information, which is: "A poll reported that 55% of 2341 American adults surveyed said they have watched digitally streamed TV programming on some type of device.
We know that 55% of 2341 American adults surveyed have watched digitally streamed TV programming on some type of device. Using this information, we can calculate the sample size required for the width of a 99%CI to be at most 0.06 irrespective of the value of (beta).Here, we can use the formula: n = [Z_{(alpha/2)} / E]^2 * P * QWhere,n = sample sizeZ_{(alpha/2)} = the z-score corresponding to the level of significance alpha/2E = margin of errorP = estimated proportion of successesQ = estimated proportion of failures1. First, let's find P, the estimated proportion of successes:P = 0.55 (given in the question)Q = 1 - P = 1 - 0.55 = 0.45Now, let's plug in the values into the formula: n = [Z_{(alpha/2)} / E]^2 * P * Qn = [Z_{(0.005)} / 0.06]^2 * 0.55 * 0.45Here, we have assumed Z_{(alpha/2)} = Z_{(0.005)}, which is the z-score corresponding to the level of significance alpha/2 for a standard normal distribution.2.
Now, we can solve for n by substituting Z_{(0.005)} = 2.58 and simplifying:n = [2.58 / 0.06]^2 * 0.55 * 0.45n = 771.34...We can round this up to the nearest whole number to get the required sample size:n = 772Therefore, a sample size of at least 772 would be required for the width of a 99%CI to be at most 0.06 irrespective of the value of (beta).More than 100 words:In conclusion, the question requires us to find the sample size required for the width of a 99%CI to be at most 0.06 irrespective of the value of (beta). We are given information about a poll that reports that 55% of 2341 American adults surveyed have watched digitally streamed TV programming on some type of device.Using this information, we can apply the formula for finding the required sample size and solve for n. After plugging in the given values, we get a sample size of 772. Therefore, a sample size of at least 772 would be required for the width of a 99%CI to be at most 0.06 irrespective of the value of (beta).It's important to have a sufficiently large sample size to ensure that our estimate of the population parameter is accurate. In this case, a sample size of 772 should be large enough to provide a reasonable estimate of the proportion of American adults who have watched digitally streamed TV programming on some type of device. However, it's worth noting that other factors, such as sampling method and response bias, can also affect the accuracy of our estimate.
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Do u know this? Answer if u know
Answer:
Hi
Step-by-step explanation:
This is quadratic equation
And factorization method was use
find the rectangular equation for the surface by eliminating the parameters from the vector-valued function. r(u, v) = 3 cos(v) cos(u)i 3 cos(v) sin(u)j 5 sin(v)k
The rectangular equation for the surface by eliminating the parameters is z = (5/3) (x² + y²)/9.
To find the rectangular equation for the surface by eliminating the parameters from the vector-valued function r(u,v), follow these steps;
Step 1: Write the parametric equations in terms of x, y, and z.
Given: r(u, v) = 3 cos(v) cos(u)i + 3 cos(v) sin(u)j + 5 sin(v)k
Let x = 3 cos(v) cos(u), y = 3 cos(v) sin(u), and z = 5 sin(v)
So, the parametric equations become; x = 3 cos(v) cos(u) y = 3 cos(v) sin(u) z = 5 sin(v)
Step 2: Eliminate the parameter u from the x and y equations.
Squaring both sides of the x equation and adding it to the y equation squared gives; x² + y² = 9 cos²(v) ...(1)
Step 3: Express cos²(v) in terms of x and y. Dividing both sides of equation (1) by 9 gives;
cos²(v) = (x² + y²)/9
Substituting this value of cos²(v) into the z equation gives; z = (5/3) (x² + y²)/9
So, the rectangular equation for the surface by eliminating the parameters from the vector-valued function is z = (5/3) (x² + y²)/9.
The rectangular equation for the surface by eliminating the parameters from the vector-valued function is found.
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Please, show work clearly and graph.
1. For a population of cans of cocoa beans marked "12 ounces", a sample of 36 cans was selected and the contents of each can was weighed. The sample revealed a mean of 11.9 ounces with a sample standa
The 95% confidence interval for the true mean weight of cocoa beans contained in cans is [11.824, 11.976] ounces.
Confidence level = 95%The degree of freedom (df) = n - 1 = 36 - 1 = 35
From the t-table, we can find the value of t for a 95% confidence level and 35 degrees of freedom:
t = 2.028Now, we can use the formula to calculate the confidence interval:
CI = X ± t(α/2) × s/√n
Where,CI = Confidence interval
X = Sample meant
= t-valueα
= significance level (1 - confidence level)
= 0.05/2
= 0.025s
= sample standard deviation
n = sample size
Putting the values, CI = 11.9 ± 2.028 × 0.21/√36
= 11.9 ± 0.076 ounce
Therefore, the 95% confidence interval for the true mean weight of cocoa beans contained in cans is [11.824, 11.976] ounces.
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Find a sine or cosine function for the given graph. Leave your answers in exact form (i.e. no decimal approximations). If necessary, type pi for π. (a) 5- 4 3 2 + 20 -19 -18 -17 -16 -15 -14 -13 -12 -
The midline of the function is given by y = 5. Also, the maximum value of the function is 20 and the minimum value is -4.A sine or cosine function can be written as follows:
Given the graph: Find a sine or cosine function for the given graph: the given graph is as follows:Given that the graph completes one cycle between x = -19 and x = -15, the period of the function is
`T = -15 - (-19) = 4`
.The midline of the function is given by y = 5. Also, the maximum value of the function is 20 and the minimum value is -4.A sine or cosine function can be written as follows:
$$f(x) = a\sin(b(x - h)) + k$$$$f(x) = a\cos(b(x - h)) + k$$
Where a is the amplitude, b is the frequency (or the reciprocal of the period), (h, k) is the midline and h is the horizontal shift of the function.To find the sine function that passes through the given points, follow these steps:Step 1: Determine the amplitude of the function by finding half the difference between the maximum and minimum values of the function.Amplitude
= `(20 - (-4))/2 = 24/2 = 12`
Therefore, `a = 12`.Step 2: Determine the frequency of the function using the period. The frequency is the reciprocal of the period, i.e., `b = 1/T`.Therefore,
`b = 1/4`.
Step 3: Determine the horizontal shift of the function using the midline. The horizontal shift is given by
`h = -19 + T/4`.
Substituting the values of T and h,
we get `h = -19 + 4/4 = -18`.
Step 4: Write the sine function in the form
`f(x) = a\sin(b(x - h)) + k`
.Substituting the values of a, b, h and k in the equation, we get:
$$f(x) = 12\sin\left(\frac{\pi}{2}(x + 18)\right) + 5$$
Therefore, the sine function that represents the given graph is
`f(x) = 12\sin\left(\frac{\pi}{2}(x + 18)\right) + 5`.
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find the union and intersection of the following family: d={dn:n∈n} , where dn=(−n,1n) for n∈n.
Given d = {dn: n ∈ N} where dn = (−n, 1/n) for n ∈ N.Find the union and intersection of the given family of d sets.
The given family of sets is {d1, d2, d3, ...} where di = (−i, 1/i) for all i ∈ N.1. To find the union of the given family of sets d, take the union of all sets in the given family of sets.i.e. d1 = (−1, 1), d2 = (−2, 1/2), d3 = (−3, 1/3), ...
Thus, the union of the given family of sets d is{d1, d2, d3, ...} = (-1, 1].Therefore, the union of the given family of sets d is (-1, 1].2. To find the intersection of the given family of sets d, take the intersection of all sets in the given family of sets .i.e. d1 = (−1, 1), d2 = (−2, 1/2), d3 = (−3, 1/3), ...Thus, the intersection of the given family of sets d is{d1, d2, d3, ...} = Ø. Therefore, the intersection of the given family of sets d is empty.
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Let X be a random variable with pdf fx (x) = Сx¯¤, x ≥ 1. If a = 2, C = ? If a = 3, C = ? E (X) = ? (for a = 3)
For a random variable; we found that C = 1 when a = 2, when a = 3, E(X) = 1.
To obtain the value of C when a = 2, we need to calculate the normalization constant by integrating the probability density function (pdf) over its entire range and setting it equal to 1.
Given that fx(x) = Cx^(-a), where a = 2, we have:
∫(from 1 to ∞) Cx^(-2) dx = 1
To integrate this expression, we can use the power rule of integration:
C * ∫(from 1 to ∞) x^(-2) dx = 1
C * [-x^(-1)](from 1 to ∞) = 1
C * [(-1/∞) - (-1/1)] = 1
C * (0 + 1) = 1
C = 1
Therefore, when a = 2, C = 1.
To find E(X) when a = 3, we need to calculate the expected value or the mean of the random variable X.
The formula for the expected value is:
E(X) = ∫(from -∞ to ∞) x * fx(x) dx
Substituting fx(x) = Cx^(-a) and a = 3, we have:
E(X) = ∫(from 1 to ∞) x * Cx^(-3) dx
E(X) = C * ∫(from 1 to ∞) x^(-2) dx
Using the power rule of integration:
E(X) = C * [-x^(-1)](from 1 to ∞)
E(X) = C * (0 + 1)
E(X) = C
Since we found that C = 1 when a = 2, when a = 3, E(X) = 1.
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3 2 points If a CEO claims that .35 of the organization's employees hold an advanced degree, .60 hold a 4-year degree, and .05 do not have a college degree, the null hypothesis would be that they are
The correct option is A) in agreement with the population proportions.
If a CEO claims that .35 of the organization's employees hold an advanced degree, .60 hold a 4-year degree, and .05 do not have a college degree, the null hypothesis would be that they are in agreement with the population proportions. The null hypothesis is represented by H0 and it is used to indicate that there is no significant difference between a proposed value and a statistically significant value. Null hypothesis is a hypothesis which shows that there is no relationship between two measured variables. The given question states that the CEO claims that .35 of the organization's employees hold an advanced degree, .60 hold a 4-year degree, and .05 do not have a college degree. Therefore, the null hypothesis would be that they are in agreement with the population proportions. Hence, the null hypothesis would be "The proportions claimed by the CEO are accurate and they are in agreement with the actual population proportions."
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the terminal point p(x, y) determined by a real number t is given. find sin(t), cos(t), and tan(t). − 1 3 , 2 2 3
The terminal point P(x, y) determined by a real number t is given. Find sin(t), cos(t), and tan(t) in this case: −13, 223.Let r be the radius of the terminal point P(x, y) and let θ be the angle in standard position that the terminal side of P(x, y) makes with the x-axis, measured in radians.
Then:r = √(x² + y²)θ = arctan(y / x)if x > 0 or y > 0θ = arctan(y / x) + πif x < 0 or y > 0θ = arctan(y / x) + 2πif x < 0 or y < 0By using this formula:r = √(x² + y²)= √((-13)² + (223)²)= √(169 + 49,729)= √49,898.θ = arctan(y / x)θ = arctan(223 / (-13))θ = - 1.6644So, we can use the angle in quadrant II and the value of r to determine the sine, cosine, and tangent of angle t.
We know that sinθ = y / rsin(-1.6644) = 223 / √49,898sin(-1.6644) ≈ - 0.9848Also, cosθ = x / rcos(-1.6644) = - 13 / √49,898cos(-1.6644) ≈ - 0.1737Finally, tanθ = y / xtan(-1.6644) = 223 / (-13)tan(-1.6644) ≈ - 17.1532Therefore:sin(t) ≈ - 0.9848cos(t) ≈ - 0.1737tan(t) ≈ - 17.1532
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4x^2 is the GCF of this polynomial.
20x^2y + 56x^3 – ?
Which could be the mystery term?
A. 22x^3
B. 24x^2y
C. 26x^2y
D. 28y^3
The mystery term in the polynomial [tex]20x^2y + 56x^3\ is\ 24x^2y[/tex], making option B the correct choice.
To determine the mystery term in the polynomial [tex]20x^2y + 56x^3[/tex], we need to find the term that, when added to [tex]20x^2y[/tex], gives us the original polynomial. Since the greatest common factor (GCF) is [tex]4x^2[/tex], we can factor it out from each term:
[tex]20x^2y = 4x^2 * 5y[/tex]
[tex]56x^3 = 4x^2 * 14x[/tex]
Now, let's compare the mystery term options:
A. [tex]22x^3[/tex]: This term does not have the same GCF of [tex]4x^2[/tex], so it cannot be the mystery term.
B. [tex]24x^2y[/tex]: This term does have the same GCF of [tex]4x^2[/tex], so it could be the mystery term.
C. [tex]26x^2y[/tex]: This term does not have the same GCF of [tex]4x^2[/tex], so it cannot be the mystery term.
D. [tex]28y^3[/tex]: This term does not have any [tex]x^2[/tex], so it cannot be the mystery term.
Therefore, the possible mystery term is option B: [tex]24x^2y.[/tex]
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A random sample survey of 80 individuals asked them how many fast food meals they had eaten the previous day. The sample mean was 0.82. Assuming that the number of fast food meals eaten by an individu
The 95% confidence interval for the unknown population mean of fast food meals eaten per day is calculated to be [0.601, 1.039]. The upper bound for this confidence interval is 1.039.
To calculate the confidence interval, we can use the formula:
Confidence Interval = sample mean ± (critical value × standard error)
First, we need to determine the critical value associated with a 95% confidence level.
For a sample size of 80, the critical value is approximately 1.96.
Next, we calculate the standard error, which represents the standard deviation of the sample mean. It can be found using the formula:
Standard Error = standard deviation / √(sample size)
In this case, the standard deviation is given as 1.08, and the sample size is 80. Thus, the standard error is,
⇒ 1.08 / √(80) ≈ 0.121.
Now we can substitute the values into the formula:
Confidence Interval = 0.82 ± (1.96 × 0.121)
Calculating the upper bound:
Upper Bound = 0.82 + (1.96 × 0.121) = 0.82 + 0.237 = 1.039
Therefore, the upper bound for the 95% confidence interval is 1.039. This means that we can be 95% confident that the true population mean falls below 1.039 based on the information obtained from the sample.
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Complete question is,
A random sample survey of 80 individuals asked them how many fast food meals they had eaten the previous day. The sample mean was 0.82. Assuming that the number of fast food meals eaten by an individual per day is normally distributed with a standard deviation of 1.08.
Calculate the 95% confidence interval for the unknown population mean.
What is the upper bound for this confidence interval?
Suppose heights of 6th graders are normally distributed with mean 159.6 and standard deviation 5.4 What is the 84.13th percentile of height? Answer:
The corresponding height value of 84.13th percentile is 165.
Given data:
Mean, µ = 159.6
Standard deviation, σ = 5.4
The percentile value, P = 84.13th percentile
To find: The corresponding height value of 84.13th percentile
We know that the z-score formula is given by `z = (x - µ)/σ`
Where x is the height value
We need to find the height value corresponding to the given percentile value. For this, we need to use the z-score table.
The given percentile value, P = 84.13%
P can also be written as P = 0.8413 (by converting into decimal)
From the z-score table, the corresponding z-score of P = 0.8413 is given by
z = 1.0 (approximately)
Now, putting the values in the z-score formula, we get:
z = (x - µ)/σ
=> 1.0 = (x - 159.6)/5.4
=> x - 159.6 = 5.4 × 1.0
=> x - 159.6 = 5.4
=> x = 159.6 + 5.4
=> x = 165
Therefore, the corresponding height value of 84.13th percentile is 165. Answer: 165.
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B. Select one quantitative, discrete variable that you find most interesting, and you would like to interpret. 1. Next, you will describe and interpret what is going on with this quantitative, discret
A quantitative, discrete variable can only take on integer values, and that is expressed in numerical terms. An example of such a variable could be the number of cars sold in a day by a dealer. In this example, it's easy to see that the variable is quantitative, expressed in numerical terms, and it is discrete, as it can only take on integer values.
The most interesting quantitative, discrete variable is the number of people who use the subway on a given day in New York City. This variable can be used to determine the efficiency of the subway system. To interpret this variable, it's essential to consider several factors, such as the time of day, the day of the week, and the location of the subway station.
To interpret this variable, it's necessary to consider the data over a more extended period, such as a month or a year. By doing this, it's possible to identify trends and patterns that can be used to improve the efficiency of the subway system. For example, if there is a significant increase in the number of people using the subway on a particular day of the week, this could indicate that there is a need for additional trains or other factors causing congestion.
Similarly, if there is a significant decrease in the number of people using the subway on a particular day of the week, this could indicate that there are other forms of transportation that are more efficient other factors causing people to avoid the subway.
The number of people who use the subway in a given day is a quantitative, discrete variable that is important for understanding the efficiency of the subway system. By analyzing this variable over a more extended period, it's possible to identify trends and patterns that can be used to improve the efficiency of the subway system.
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The rate constant for the second-order reaction 2 NO2(g) → 2 NO(g) + O2(g) is 0.54 M-1-s-1 at 300.°C. How long (in seconds) would it take for the concentration of NO 2 to decrease from 0.63 M to 0.30 M?
To find the time it takes for the concentration of NO2 to decrease from 0.63 M to 0.30 M in a second-order reaction, we can use the integrated rate law for a second-order reaction:
1/[NO2] - 1/[NO2]₀ = kt
Where [NO2] is the final concentration of NO2, [NO2]₀ is the initial concentration of NO2, k is the rate constant, and t is the time.
Rearranging the equation, we have:
t = 1/(k([NO2] - [NO2]₀))
Given:
[NO2]₀ = 0.63 M (initial concentration of NO2)
[NO2] = 0.30 M (final concentration of NO2)
k = 0.54 M^(-1)s^(-1) (rate constant)
Substituting the values into the equation:
t = 1/(0.54 M^(-1)s^(-1) * (0.30 M - 0.63 M))
Simplifying:
t = 1/(0.54 M^(-1)s^(-1) * (-0.33 M))
t = -1/(0.54 * -0.33) s
Taking the absolute value:
t ≈ 5.46 s
Therefore, it would take approximately 5.46 seconds for the concentration of NO2 to decrease from 0.63 M to 0.30 M in the given second-order reaction.
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.Find the margin of error for the given values of c, s, and n.
c = 0.90, s = 2.6, n = 64. (Round to three decimal places as needed.)
The margin of error is found approximately 0.546 for the given values of c, s, and n.
Margin of Error:The margin of error (ME) is the degree of imprecision or uncertainty present in a sampling technique's outcomes. The statistic is expressed as the difference between a survey or test result and the actual result that is likely to be achieved in the entire population being examined.
It is calculated as follows: ME = z*σ/√n, where z* is the z-score value for the level of confidence needed, σ is the population standard deviation, and n is the sample size. Here is the solution to the provided problem.
Find the margin of error for the given values of c, s, and n.c = 0.90, s = 2.6, n = 64.
Step 1: The level of confidence is given by c = 0.90.
Step 2: We know the sample size n = 64.
Step 3: We can now apply the formula to calculate the margin of error:ME = z*σ/√n.
Step 4: We must calculate the critical value z* for the given level of confidence. We can use the standard normal distribution table or calculator to obtain the value.
z* = 1.645 (For 90% level of confidence).
Step 5: We need to determine the standard deviation (σ) of the population, which is not given in the problem. As a result, we can use the sample standard deviation s as an estimate of the population standard deviation.σ ≈ s = 2.6.
Step 6: Substitute all known values into the formula.
ME = z*σ/√n = 1.645*2.6/√64 = 0.5463.
Step 7: Round the margin of error to three decimal places.ME ≈ 0.546 (rounded to three decimal places).
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What is the probability that the sample proportion is between 0.2 and 0.42?
The probability that the sample proportion is between 0.2 and 0.42 can be calculated using the standard normal distribution.
To calculate the probability, we need to assume that the sample proportion follows a normal distribution. This assumption holds true when the sample size is sufficiently large and the conditions for the central limit theorem are met.
First, we need to calculate the standard error of the sample proportion. The standard error is the standard deviation of the sampling distribution of the sample proportion and is given by the formula sqrt(p(1-p)/n), where p is the estimated proportion and n is the sample size.
Next, we convert the sample proportion range into z-scores using the formula z = (x - p) / SE, where x is the given proportion and SE is the standard error. In this case, we use z-scores of 0.2 and 0.42.
Once we have the z-scores, we can use a standard normal distribution table or a statistical software to find the corresponding probabilities. The probability of the sample proportion falling between 0.2 and 0.42 is equal to the difference between the two calculated probabilities.
Alternatively, we can use the z-table to find the individual probabilities and subtract them. The z-table provides the cumulative probabilities up to a certain z-score. By subtracting the lower probability from the higher probability, we can find the desired probability.
In conclusion, the probability that the sample proportion is between 0.2 and 0.42 can be calculated using the standard normal distribution and z-scores. This probability represents the likelihood of observing a sample proportion within the specified range.
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