The probabilities are, a) More than 75 = 0.2798 b) Less than 60 = 0.2525 c) Between 65 and 70 = 0.1662 d) Less than 50 = 0.0668
Given, Mean (μ) = 68 Standard deviation (σ) = 12
We need to find the probability that one student is selected at random will get,
a) More than 75z = (75 - 68) / 12= 0.5833P(z > 0.5833) = 1 - P(z ≤ 0.5833)From the standard normal distribution table, we have the value of P(z ≤ 0.58) as 0.7202
Therefore, P(z > 0.5833) = 1 - 0.7202 = 0.2798
b) Less than 60z = (60 - 68) / 12= -0.6667P(z < -0.6667)
From the standard normal distribution table, we have the value of P(z < -0.6667) as 0.2525
Therefore, P(z < -0.6667) = 0.2525
c) Between 65 and 70
z1 = (65 - 68) / 12= -0.25z2 = (70 - 68) / 12= 0.1667P(-0.25 < z < 0.1667) = P(z < 0.1667) - P(z < -0.25)
From the standard normal distribution table, we have the value of P(z < -0.25) as 0.4013 and P(z < 0.1667) as 0.5675
Therefore, P(-0.25 < z < 0.1667) = 0.5675 - 0.4013 = 0.1662
d) Less than 50z = (50 - 68) / 12= -1.5P(z < -1.5) From the standard normal distribution table, we have the value of P(z < -1.5) as 0.0668
Therefore, P(z < -1.5) = 0.0668
Hence, the probabilities are, a) More than 75 = 0.2798 b) Less than 60 = 0.2525 c) Between 65 and 70 = 0.1662 d) Less than 50 = 0.0668
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7. (1 mark) The p-value is smaller than 0.05 ___
- true
- false
8. (1 mark) We decide that ___
- p value is greater than 0.05, therefore we do not reject the
null hypothesis
- p value is less than 0.0
The p-value is smaller than 0.05 is true. If the p-value is smaller than 0.05, we reject the null hypothesis (H0). A small p-value indicates that the probability of obtaining such a result by chance is low.
When the p-value is less than the level of significance (0.05), we reject the null hypothesis (H0) and assume that the alternative hypothesis (Ha) is true. Thus, it can be concluded that if the p-value is less than 0.05, then there is sufficient evidence to support the alternative hypothesis and reject the null hypothesis.8. We decide that p-value is less than 0.05. Therefore, we reject the null hypothesis.
When the p-value is less than 0.05, the null hypothesis is rejected, and it is assumed that the alternative hypothesis is valid. The alternative hypothesis can be one-tailed or two-tailed. If the alternative hypothesis is one-tailed, then the critical region is in one tail of the distribution. In contrast, if the alternative hypothesis is two-tailed, the critical region is in both tails of the distribution. Thus, when the p-value is less than 0.05, we reject the null hypothesis and accept the alternative hypothesis.
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22
Refer to the accompanying table, which describes the number of adults in groups of five who reported sleepwalking. Find the mean and standard deviation for the umbers of sleepwalkers in groups of five
The mean is 1.4 and , the standard deviation is 0.6
The mean is calculated by taking the sum of all the values in the table and dividing by the number of values. In this case, the sum of all the values is 22 and there are 22 values.
The standard deviation is calculated by taking the square root of the variance. The variance is calculated by taking the sum of the squared differences between each value and the mean, and dividing by the number of values minus 1. In this case, the variance is 0.36.
In other words, in a group of five adults, we would expect to see 1.4 adults sleepwalking on average. There is also a standard deviation of 0.6, which means that the number of sleepwalkers in a group of five is likely to be between 0.8 and 2.0.
It is important to note that these are just estimates, and the actual number of sleepwalkers in a group of five could be any number.
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Note: The complete question is : Refer to the accompanying table, which describes the number of adults in groups of five who reported sleepwalking. Find the mean and standard deviation for the numbers of sleepwalkers in groups of five.
The table is as follows:
Number of sleepwalkers | Probability
---------------------- | --------
0 | 0.172
1 | 0.363
2 | 0.306
3 | 0.129
4 | 0.027
5 | 0.002
Consider the following data for a dependent variable y and two independent variables, ₁ and 2; for these data SST = 15,188.1, and SSR 14,228.1. = x1 X2 Y 13 94 10 109 18 113 17 178 6 95 20 176 7 170
Here, we are given the data for a dependent variable Y and two independent variables ₁ and 2.
For these data SST = 15,188.1, and SSR 14,228.1.The following is a model to regress Y on ₁ and 2:Y = β₀ + β₁₁ + β₂₂ +
Now, we can find the SSE using SST and SSR.SSE = SST - SSR= 15,188.1 - 14,228.1= 960.0
Summary: SSE is a measure of how well a linear regression model fits the data. It calculates the sum of the squared residuals, which is the difference between the predicted values and the actual values.
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7 and 8 please. This is a list of criminal record convictions of a cohort of 395 boys obtained from a prospective epidemiological study. Ntmibetaticometeuone 0 265 49 1.Calculate the mean number of convictions for this sample 2.Calculate the variance for the number of convictions in this sample. 3.Calculate the standard deviation for the number of convictions in this sample. 4.Calculate the standard error for the number of convictions in this sample 5. State the range for the number of convictions in this sample 6. Calculate the proportion of each category i.e.number of convictions). 7. Calculate the cumulative relative frequency for the data 8. Graph the cumulative frequency distribution. 1 21 19 18 10 2 10 11 12 13 1
The answers are =
1) 6.06, 2) the variance is approximately 11.82, 3) the standard deviation for the number of convictions in this sample is approximately 3.44, 4) the standard error for the number of convictions in this sample is approximately 0.173, 5) the range for the number of convictions in this sample is 14, 6) Proportion = Frequency / 395, 7) Cumulative Relative Frequency = Proportion for Category + Proportion for Category-1 + ... + Proportion for Category-14.
1) To calculate the mean number of convictions, you need to multiply each number of convictions by its corresponding frequency, sum up the products, and then divide by the total number of boys in the sample:
Mean = (0 × 265 + 1 × 49 + 2 × 1 + 3 × 21 + 4 × 19 + 5 × 18 + 6 × 10 + 7 × 2 + 8 × 2 + 9 × 4 + 10 × 2 + 11 × 1 + 12 × 4 + 13 × 3 + 14 × 1) / 395 = 6.06
2) To calculate the variance for the number of convictions, you need to calculate the squared difference between each number of convictions and the mean, multiply each squared difference by its corresponding frequency, sum up the products, and then divide by the total number of boys in the sample:
Variance = [(0 - Mean)² × 265 + (1 - Mean)² × 49 + (2 - Mean)² × 1 + (3 - Mean)² × 21 + (4 - Mean)² × 19 + (5 - Mean)² × 18 + (6 - Mean)² × 10 + (7 - Mean)² × 2 + (8 - Mean)² × 2 + (9 - Mean)² × 4 + (10 - Mean)² × 2 + (11 - Mean)² × 1 + (12 - Mean)² × 4 + (13 - Mean)² × 3 + (14 - Mean)² × 1] / 395
After performing the calculations, the variance is approximately 11.82.
3) To calculate the standard deviation for the number of convictions, you take the square root of the variance:
Standard Deviation = √Variance
4) To calculate the standard error for the number of convictions, you divide the standard deviation by the square root of the total number of boys in the sample:
Standard Error = Standard Deviation / √395
5) The range for the number of convictions is the difference between the maximum and minimum number of convictions in the sample.
From the given data, it appears that the range is 14 (maximum - minimum).
6) To calculate the proportion of each category (number of convictions), you divide the frequency of each category by the total number of boys in the sample (395).
Proportion = Frequency / 395
7) To calculate the cumulative relative frequency for the data, you sum up the proportions for each category in order.
The cumulative relative frequency for each category is the sum of the proportions up to that category.
Cumulative Relative Frequency = Proportion for Category + Proportion for Category-1 + ... + Proportion for Category-14
8) To graph the cumulative frequency distribution, you can plot the number of convictions on the x-axis and the cumulative relative frequency on the y-axis.
Each category (number of convictions) will have a corresponding point on the graph, and you can connect the points to visualize the cumulative frequency distribution.
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for [infinity] 13 n10 n = 1 , since f(x) = 13 x10 is continuous, positive, and decreasing on [1, [infinity]), we consider the following. (if the quantity diverges, enter diverges.)
Given a series [infinity] 13n10n=1. Since f(x) = 13x10 is continuous, positive and decreasing on [1, [infinity]), we have to determine whether the series converges or diverges.
We know that for a decreasing series an, the integral test states that if the integral ∫f(x)dx from 1 to [infinity] converges, then the series also converges. Let's consider the integral ∫f(x)dx from 1 to [infinity]. ∫f(x)dx = ∫13x10dx from 1 to [infinity] ,
= [13/110] [x11] from 1 to [infinity] = [13/110] lim x-> [infinity] x11 - [13/110] (1) = [13/110] [infinity] - [13/110]
Therefore, ∫f(x)dx diverges since the limit does not exist and the integral has an infinite value.
Hence, by the integral test, we can conclude that the series [infinity] 13n10n=1 diverges. Hence, the answer is, The given series [infinity] 13n10n=1 diverges.
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: 38. In a survey of 500 students of a college, it was found that 49% liked watching football, 53% liked watching hockey and 62% liked watching basketball. Also, 27% liked watching football and hocke both, 29% liked watching basketball and hockey both and 28% liked watching football and basketball both. 5% liked watching none of these games. a) Draw a Venn diagram to represent the survey results. (3 marks) b) How many students like watching all the three games? (2 marks) 14
(a) The Venn-Diagram to represent the results of the survey is shown below.
(b) The number of students who like watching all 3-games are 75.
Part (a) : Let "F" denote students who like to watch football,
Let "H" denote students who like to watch hockey,
Let "B" denote students who like to watch basketball,
The Venn diagram as per the information is shown below.
Part (b) : To calculate the number of students who like watching all three games using information, we denote the number of students who like watching all three games as X.
From the given information:
F = 0.49 × 500 = 245 (49% of 500)
H = 0.53 × 500 = 265 (53% of 500)
B = 0.62 × 500 = 310 (62% of 500)
FH = 0.27 × 500 = 135 (27% of 500)
BH = 0.29 × 500 = 145 (29% of 500)
FB = 0.28 × 500 = 140 (28% of 500)
We use the principle of inclusion-exclusion to find X:
X = FH + BH + FB - (F + H + B) + Total
Since we are given that 5% of the students liked none of the games, the number of students who liked none of the games is:
None = 0.05 × 500 = 25 (5% of 500)
We know that the total-students is 500.
Substituting the values,
We get,
X = 135 + 145 + 140 - (245 + 265 + 310) + 500 - 25
X = 75,
Therefore, there are 75 students who like watching all-three games (football, hockey, and basketball).
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Let X be the number of 1's and Y the number of 2's that occur in N rolls of a fair die.
a. Find Cov (X,Y) and\rho(X,Y)
b. Suppose that we have N = 1000. What should Cov (X,Y) and\rho(X,Y) be in this case?
a. The covariance of (X, Y) is o and the coefficient of correlation is 0
b. The value covariance of (X, Y) and coefficient of correlation is 0.
What is Covariance (X, Y) and ρ(X, Y)?a. The covariance (Cov) between X and Y can be calculated using the formula:
Cov(X, Y) = E(XY) - E(X)E(Y)
Since we are rolling a fair die, the probability of getting a 1 is 1/6 and the probability of getting a 2 is 1/6.
E(X) = N * P(X = 1) = N * (1/6)
E(Y) = N * P(Y = 2) = N * (1/6)
To calculate E(XY), we need to consider the joint probabilities of X and Y. Since X and Y are counting the number of 1's and 2's respectively, they are independent random variables.
E(XY) = E(X)E(Y) = N * (1/6) * N * (1/6) = N^2/36
Therefore, Cov(X, Y) = E(XY) - E(X)E(Y) = N^2/36 - (N/6)(N/6) = N^2/36 - N^2/36 = 0
The correlation coefficient (ρ) between X and Y can be calculated as:
ρ(X, Y) = Cov(X, Y) / (σ(X)σ(Y))
Since we are rolling a fair die, the variance of X and Y can be calculated as follows:
σ(X)^2 = N * P(X = 1)(1 - P(X = 1)) = N * (1/6)(5/6)
σ(Y)^2 = N * P(Y = 2)(1 - P(Y = 2)) = N * (1/6)(5/6)
ρ(X, Y) = Cov(X, Y) / (σ(X)σ(Y)) = 0 / (√(N * (1/6)(5/6)) * √(N * (1/6)(5/6)))
= 0 / (√(N^2/36) * √(N^2/36))
= 0 / (N/6 * N/6)
= 0
b. If N = 1000, Cov(X, Y) and ρ(X, Y) would still be 0. This is because X and Y are independent random variables in this case, and the covariance and correlation would be 0 regardless of the value of N.
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Determine the point(s), if any, at which the graph of the function has a horizontal tangent line. (If an answer does not exist, enter DNE.)
y=x4-2x2+9
(x,y)= (,) smallest x value
(x,y)= (,)
(x,y)= (,) largest x value
The given function is y=x⁴ - 2x² + 9. To find the point(s), if any, at which the graph of the function has a horizontal domain tangent line, we first need to find the derivative of the function.
We can then set the derivative equal to zero to find any critical points where the slope is zero, which indicates a horizontal tangent line. The derivative of the given function is:y' = 4x³ - 4xThe slope of a horizontal line is zero. Hence we can set the derivative equal to zero to find the critical points:4x³ - 4x = 0Factor out 4x:x(4x² - 4) = 04x(x² - 1) = 0Factor completely:x = 0 or x = ±1The critical points are x = 0, x = -1, and x = 1.
Now we need to find the corresponding y-values at these critical points to determine whether the graph has a horizontal tangent line at each point. For x = 0:y = x⁴ - 2x² + 9y = 0⁴ - 2(0)² + 9y = 9The point (0, 9) is a candidate for a horizontal tangent line.For x = -1:y = x⁴ - 2x² + 9y = (-1)⁴ - 2(-1)² + 9y = 12The point (-1, 12) is a candidate for a horizontal tangent line.For x = 1:y = x⁴ - 2x² + 9y = (1)⁴ - 2(1)² + 9y = 8The point (1, 8) is a candidate for a horizontal tangent line. Therefore, the points at which the graph of the function has a horizontal tangent line are:(0, 9)(-1, 12)(1, 8)The smallest x-value is x = -1 and the corresponding y-value is y = 12. Therefore, (x, y) = (-1, 12).The largest x-value is x = 1 and the corresponding y-value is y = 8. Therefore, (x, y) = (1, 8).
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Find the local maximum and local minimum values of f using both the First and Second Derivative Tests. f(x) = 3 + 6x2 - 4x3 = local maximum value x local minimum value x
To find the local maximum and local minimum values of the function f(x) = 3 + 6[tex]x^2[/tex] - 4[tex]x^3[/tex], we can use the First and Second Derivative Tests.
The critical points of the function can be determined by finding where the first derivative is equal to zero or undefined. Then, by analyzing the sign of the second derivative at these critical points, we can classify them as local maximum or local minimum points.
To find the critical points, we first calculate the first derivative of f(x) as f'(x) = 12x - 12[tex]x^2[/tex]. Setting this derivative equal to zero, we solve the equation 12x - 12[tex]x^2[/tex] = 0. Factoring out 12x, we get 12x(1 - x) = 0. So, the critical points occur at x = 0 and x = 1.
Next, we find the second derivative of f(x) as f''(x) = 12 - 24x. Evaluating the second derivative at the critical points, we have f''(0) = 12 and f''(1) = -12.
By the First Derivative Test, we can determine that at x = 0, the function changes from decreasing to increasing, indicating a local minimum point. Similarly, at x = 1, the function changes from increasing to decreasing, indicating a local maximum point.
Therefore, the local minimum occurs at x = 0, and the local maximum occurs at x = 1 for the function f(x) = 3 + 6[tex]x^2[/tex] - 4[tex]x^3[/tex].
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If the average daily income for small grocery markets in Riyadh
is 6000 riyals, and the standard deviation is 900 riyals, in a
sample of 600 markets find the standard error of the mean?
3.75
The standard error of the mean for the given sample of 600 small grocery markets in Riyadh is approximately 36.75 riyals.
To find the standard error of the mean, we divide the standard deviation by the square root of the sample size.
Given:
Average daily income (mean) = 6000 riyals
Standard deviation = 900 riyals
Sample size = 600
The formula to calculate the standard error of the mean is:
Standard Error = Standard Deviation / √(Sample Size)
Plugging in the values:
Standard Error = 900 / √600
Calculating the square root of 600:
√600 ≈ 24.49
Standard Error = 900 / 24.49
Standard Error ≈ 36.75
Therefore, the standard error of the mean for the given sample of 600 small grocery markets in Riyadh is approximately 36.75 riyals.
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If one card is drawn from a deck, find the probability of getting, a 10 or a Jack. Write the fraction in lowest terms. O a. 8 13 Ob. 2 13 O c. O d. 1 18-18 7 26 26
The probability of getting a 10 or a Jack is 2/13. The correct answer is option B.
The probability of getting a 10 or a Jack from a deck of cards can be calculated by finding the number of favorable outcomes (cards that are either a 10 or a Jack) and dividing it by the total number of possible outcomes (total number of cards in the deck).
In a standard deck of 52 cards, there are 4 10s and 4 Jacks. Therefore, the number of favorable outcomes is 4 + 4 = 8.
The total number of possible outcomes is 52 (since there are 52 cards in the deck).
Therefore, the probability of getting a 10 or a Jack is 8/52, which can be simplified to 2/13.
So the correct answer is option B: 2/13.
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what is the explicit rule for the geometric sequence? 9,6,4,83,… enter your answer in the box.
The explicit rule for the geometric sequence 9,6,4,83,… is [tex]a_n = 9(\frac{1}{3} )^{n-1}[/tex].
How to calculate the nth term of a geometric sequence?In Mathematics and Geometry, the nth term of a geometric sequence can be calculated by using this mathematical equation (formula):
aₙ = a₁rⁿ⁻¹
Where:
aₙ represents the nth term of a geometric sequence.r represents the common ratio.a₁ represents the first term of a geometric sequence.Next, we would determine the common ratio as follows;
Common ratio, r = a₂/a₁
Common ratio, r = 6/9
Common ratio, r = 2/3
For the explicit rule, we have:
aₙ = a₁rⁿ⁻¹
[tex]a_n = 9(\frac{1}{3} )^{n-1}[/tex]
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about 96% of the population have iq scores that are within _____ points above or below 100. 30 10 50 70
About 96% of the population has IQ scores that are within 30 points above or below 100.
In this case, we are given the percentage (96%) and asked to determine the range of IQ scores that fall within that percentage.
Since IQ scores are typically distributed around a mean of 100 with a standard deviation of 15, we can use the concept of standard deviations to calculate the range.
To find the range that covers approximately 96% of the population, we need to consider the number of standard deviations that encompass this percentage.
In a normal distribution, about 95% of the data falls within 2 standard deviations of the mean. Therefore, 96% would be slightly larger than 2 standard deviations.
Given that the standard deviation for IQ scores is approximately 15, we can multiply 15 by 2 to get 30. This means that about 96% of the population has IQ scores that are within 30 points above or below the mean score of 100.
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Test the claim that the proportion of people who own cats is
smaller than 20% at the 0.005 significance level. The null and
alternative hypothesis would be:
H 0 : p = 0.2 H 1 : p < 0.2
H 0 : μ ≤
In hypothesis testing, the null hypothesis is always the initial statement to be tested. In the case of the problem above, the null hypothesis (H0) is that the proportion of people who own cats is equal to 20% or p = 0.2.
Given, The null hypothesis is, H0 : p = 0.2
The alternative hypothesis is, H1 : p < 0.2
Where p represents the proportion of people who own cats.
Since this is a left-tailed test, the p-value is the area to the left of the test statistic on the standard normal distribution.
Using a calculator, we can find that the p-value is approximately 0.0063.
Since this p-value is less than the significance level of 0.005, we reject the null hypothesis and conclude that there is sufficient evidence to suggest that the proportion of people who own cats is less than 20%.
Summary : The null hypothesis (H0) is that the proportion of people who own cats is equal to 20% or p = 0.2. The alternative hypothesis (H1), on the other hand, is that the proportion of people who own cats is less than 20%, or p < 0.2.Using a calculator, we can find that the p-value is approximately 0.0063. Since this p-value is less than the significance level of 0.005, we reject the null hypothesis and conclude that there is sufficient evidence to suggest that the proportion of people who own cats is less than 20%.
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I need with plissds operations.. area= perimeter=
The perimeter of the solid figure shown is 57.5 cm
What is an equation?An equation is an expression that shows how numbers and variables are related to each other using mathematical operations.
The perimeter of a solid figure is gotten by summing the individual length of each side.
For the figure shown:
Perimeter = 11.1 + 11.1 + 11.1 + 12.1 + 12.1 = 57.5 cm
The perimeter is 57.5 cm
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find an equation of the set of all points equidistant from the points a(−2, 4, 4) and b(5, 2, −3). describe the set.
The set of all points equidistant from the points A(-2, 4, 4) and B(5, 2, -3) forms a plane. This plane can be described by an equation that represents the locus of points equidistant from A and B.
To find the equation of the plane, we can first calculate the midpoint M between points A and B, which is given by the coordinates (x₀, y₀, z₀) of M, where x₀ = (x₁ + x₂)/2, y₀ = (y₁ + y₂)/2, and z₀ = (z₁ + z₂)/2.
Midpoint M:
x₀ = (-2 + 5)/2 = 3/2
y₀ = (4 + 2)/2 = 3
z₀ = (4 - 3)/2 = 1/2
Next, we calculate the direction vector D from A to B, which is obtained by subtracting the coordinates of A from those of B.
Direction vector D:
dx = 5 - (-2) = 7
dy = 2 - 4 = -2
dz = -3 - 4 = -7
Using the midpoint M and the direction vector D, we can write the equation of the plane as follows:
(x - x₀)/dx = (y - y₀)/dy = (z - z₀)dz
Substituting the values we calculated earlier, the equation becomes:
(x - 3/2)/7 = (y - 3)/(-2) = (z - 1/2)/(-7)
This equation represents the set of all points equidistant from points A(-2, 4, 4) and B(5, 2, -3), and it describes a plane in three-dimensional space.
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solve for g(f(0)) if f(x) = g(x) = 2x - 1 3x− 7 4 answer: g(f(0)) = = = = = - 2
The value of g(f(0)) is -2.
To find g(f(0)), we need to first evaluate f(0) and then substitute the result into the function g(x). Given that f(x) = 2x - 1, we can find f(0) by substituting 0 for x: f(0) = 2(0) - 1 = -1.
Next, we substitute -1 into the function g(x), which is g(x) = 3x - 7. Plugging in -1 for x, we get: g(-1) = 3(-1) - 7 = -3 - 7 = -10.
Therefore, g(f(0)) = g(-1) = -10.To solve for g(f(0)), we first need to find the value of f(0). Given that f(x) = 2x - 1, we substitute 0 for x: f(0) = 2(0) - 1 = -1.
Next, we substitute the value of f(0) into the function g(x). Given that g(x) = 3x - 7, we substitute -1 for x: g(-1) = 3(-1) - 7 = -3 - 7 = -10.
Therefore, g(f(0)) = g(-1) = -10. The correct answer is -10, not -2 as stated in the question. The correct calculation shows that g(f(0)) equals -10, not -2.
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21)
22)
Assume that when adults with smartphones are randomly selected, 46% use them in meetings or classes. If 12 adult smartphone users are randomly selected, find the probability that fewer than 5 of them
The probability that fewer than 5 of them use the smartphone in meetings or classes is given as follows:
P(X < 5) = 0.2802 = 28.02%.
How to obtain the probability with the binomial distribution?The mass probability formula is defined by the equation presented as follows:
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
The parameters, along with their meaning, are presented as follows:
n is the fixed number of independent trials.p is the constant probability of a success on a single independent trial of the experiment.The parameter values for this problem are given as follows:
p = 0.46, n = 12.
The probability that less than 5 of them use the phone is given as follows:
P(X < 5) = P(X = 0) + P(X = 1) + P(X = 2) + P(X = 3) + P(X = 4).
Using a calculator with the parameters above, the probability is:
P(X < 5) = 0.2802 = 28.02%.
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Consider the area of your garden. If you want
to plant 8 items in your garden, and each item requires 2 sq. ft.
of space, will you have enough space in your garden for the 8
vegetable plants? Show all
If your garden area is equal to or larger than 16 square feet, then you will have enough space for all the plants. If your garden is less than 16 square feet, you won't have enough space for all the 8 plants.
How to get the space for the gardenThe calculation to know how many square feet you need for your 8 items is straightforward. Each item requires 2 sq. ft. of space, and you have 8 items, so you would multiply:
2 sq. ft. * 8 items = 16 sq. ft.
So, you would need 16 square feet of space in your garden to plant 8 items that each require 2 square feet.
If your garden area is equal to or larger than 16 square feet, then you will have enough space for all the plants. If your garden is less than 16 square feet, you won't have enough space for all the 8 plants.
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Determine whether the points are collinear. If so, find the line y = c0 + c1x that fits the points. (If the points are not collinear, enter NOT COLLINEAR.) (0, 2), (1, 5), (2, 8)
The slope of the line passing through any two of the points is the same, the points are collinear & the line that fits the given points is y = 3x + 2.
The given points are (0, 2), (1, 5), (2, 8).
To determine whether the points are collinear,
we can find the slope of the line passing through any two of the points and then check if the slope is the same for all the pairs of points.
Let's take (0, 2) and (1, 5) to find the slope of the line passing through them:
Slope (m) = (y₂ - y₁) / (x₂ - x₁)
= (5 - 2) / (1 - 0)
= 3 / 1
= 3Now
Let's take (1, 5) and (2, 8) to find the slope of the line passing through them:
Slope (m) = (y₂ - y₁) / (x₂ - x₁)
= (8 - 5) / (2 - 1)
= 3 / 1
= 3
Since the slope of the line passing through any two of the points is the same, the points are collinear.
To find the line y = c₀ + c₁x that fits the points,
we can use the point-slope form of the equation of a line:
y - y₁ = m(x - x₁)
We can use any of the points and the slope found above.
Let's use (0, 2):
y - 2 = 3(x - 0)
y - 2 = 3x + 0
y = 3x + 2
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To test the claim that snack choices are related to the gender of the consumer, a survey at a ball park shows this selection of snacks purchased. Test the claim using a significance level of 0.05.
Hotdog
Peanuts
Popcorn
Male
30
60
45
Female
25
25
40
The critical value is approximately 5.99.Since our test statistic (8.87) is greater than the critical value (5.99), we can reject the null hypothesis and conclude that there is evidence to suggest that snack choices are related to the gender of the consumer.
We need to test the claim that snack choices are related to the gender of the consumer, using a significance level of 0.05. This can be done using chi-squared test statistic. First step is to create the contingency table as shown below:HotdogPeanutsPopcornTotalMale306045135Female252540110Total557085245Next step is to find the expected frequencies for each cell in the contingency table.
To do this, we can use the formula:Expected frequency = (Row total x Column total) / Grand totalFor example, the expected frequency for the cell in row 1, column 1 would be:Expected frequency = (135 x 55) / 245Expected frequency = 30.27Using this formula for each cell, we can fill in the expected frequencies:HotdogPeanutsPopcornTotalMale30.27 54.41 50.32 135Female24.73 44.59 41.68 110Total55 99 92 245We can now use the chi-squared formula to calculate the test statistic:χ2 = Σ [ (O - E)2 / E ]where O = observed frequency and E = expected frequency.We can calculate each term in turn and add them up:χ2 = [ (30 - 30.27)2 / 30.27 ] + [ (60 - 54.41)2 / 54.41 ] + [ (45 - 50.32)2 / 50.32 ] + [ (25 - 24.73)2 / 24.73 ] + [ (25 - 44.59)2 / 44.59 ] + [ (40 - 41.68)2 / 41.68 ]χ2 = 0.009 + 0.585 + 0.401 + 0.003 + 6.851 + 0.022χ2 = 8.87
Finally, we need to find the critical value for chi-squared with 2 degrees of freedom and a significance level of 0.05. This can be done using a chi-squared table or a calculator. The critical value is approximately 5.99.Since our test statistic (8.87) is greater than the critical value (5.99), we can reject the null hypothesis and conclude that there is evidence to suggest that snack choices are related to the gender of the consume.
To test the claim that snack choices are related to the gender of the consumer, we used chi-squared test statistic. We created a contingency table and calculated the expected frequencies for each cell. We then calculated the test statistic using the chi-squared formula. The critical value was found using a chi-squared table or calculator. The test statistic was greater than the critical value, so we rejected the null hypothesis and concluded that there is evidence to suggest that snack choices are related to the gender of the consumer.
The significance level was 0.05, which means that there is a 5% chance of making a Type I error (rejecting the null hypothesis when it is actually true). Therefore, we can be 95% confident that our conclusion is correct.
Snack choices are related to the gender of the consumer, based on the survey at a ball park. The chi-squared test statistic was 8.87 and the critical value was 5.99, with 2 degrees of freedom and a significance level of 0.05. We rejected the null hypothesis and concluded that there is evidence to support the claim. The significance level of 0.05 means that we can be 95% confident that our conclusion is correct.
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how many permutations of the seven letters a, b, c, d, e, f, g are there?
According to the question we have There are a total of 5040 permutations of 7 letters a, b, c, d, e, f, g.
The given problem is of permutation as we are supposed to find out the number of ways in which the letters of a word can be arranged.
The formula to find the permutations is P (n, r) = n! / (n - r)! where, n is the total number of elements to choose from and r is the number of elements that are being chosen.
Let's apply the formula to find the permutation of 7 letters from a, b, c, d, e, f, g:P(7, 7) = 7! / (7-7)! = 7! / 0! = 7 * 6 * 5 * 4 * 3 * 2 * 1 / 1 = 5040.
There are a total of 5040 permutations of 7 letters a, b, c, d, e, f, g.
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1 Minimum-norm solution to least-squares (12 points) Consider a regularized least-squares problem min || Ax − y||² + \||x|| ²/2, x where A € Rmxn is a non-zero matrix, y € Rm, and λ ≥ 0 is
In the regularized least-squares problem min [tex]|| Ax − y||² + \||x|| ²/2, x[/tex], where [tex]A € Rm x n[/tex] is a non-zero matrix, [tex]y € Rm, and λ ≥ 0[/tex] is a scalar.
We shall demonstrate that the unique minimum-norm solution x* to this problem is given by
[tex]x* = (A.T A + λI)−1 A.T y,[/tex]
where I denotes the n × n identity matrix.
Given,
[tex]min || Ax − y||² + \||x|| ²/2[/tex], x Let [tex]L(x) = || Ax − y||² + \||x|| ²/2 …[/tex](1)
Differentiate L(x) w.r.t x,
we get- [tex]dL/dx = d/dx(x^T A^T A x − x^T A^T y − y^T A x + y^T y/2 + x^T x/2)[/tex]
[tex]dL/dx = d/dx(x^T A^T A x − x^T A^T y − y^T A x + y^T y/2 + x^T x/2)[/tex]
[tex]dL/dx = (2 A^T A x − 2 A^T y + x)[/tex]
Let dL/dx = 0;
then [tex]x = A^T y − A^T A x …[/tex](2)
Multiplying both sides of equation (2) by A,
we get A x = A A^T y − A A^T A x …(3)
The given system of equations has a unique solution if and only if the matrix [tex]A A^T[/tex] is invertible. We obtain the unique solution to the equation [tex]A x = A A^T y − A A^T A x[/tex] by multiplying both sides by
[tex](A A^T + λI)−1[/tex] to get
[tex](A A^T + λI)−1 A x = (A A^T + λI)−1 (A A^T y) ...(*),[/tex]
where I denotes the n × n identity matrix.
Multiplying both sides of equation (2) by [tex](A A^T + λI)−1,[/tex]
we get [tex]x* = (A A^T + λI)−1 A^T y …[/tex](4) x* is the unique solution to the problem min [tex]|| Ax − y||² + \||x|| ²/2, x.[/tex]
It now remains to show that the solution x* is also the minimum-norm solution. We begin by observing that, since x* is the solution to (4),
we have [tex](A A^T + λI) x* = A^T y[/tex] …(5)
Multiplying both sides of equation (5) by x*,
we get [tex](A A^T + λI) x* · x* = (A^T y) · x* A A^T x* · x* + λ ||x*||² = (A^T y) · x*[/tex]
Now, since λ ≥ 0, we have λ ||x*||² ≥ 0, and so [tex]A A^T x* · x* ≤ (A^T y) · x* …(6)[/tex]
Next, suppose that x is any other vector that satisfies [tex]A x = A A^T y − A A^T A x.[/tex]
Then, multiplying both sides of equation (3) by x, we obtain [tex]A x · x = (A A^T y) · x − A A^T A x · x …(7)[/tex]
Since x satisfies [tex]A x = A A^T y − A A^T A x,[/tex]
we have [tex]A A^T A x = A A^T y − A x.[/tex]
Substituting this into equation (7), we obtain [tex]A x · x = (A A^T y) · x − (A A^T y) · x + x · x = x · x[/tex]... (8)
Equation (8) can be re-arranged as [tex]A x · x − x · x = 0[/tex],
which implies [tex]A x · x ≤ x · x …[/tex](9)
Combining inequalities (6) and (9), we get [tex]A x · x ≤ x · x ≤ A A^T x* · x*[/tex], which implies that [tex]|| x || ≤ || x* ||.[/tex]
Therefore, x* is the unique minimum-norm solution to the problem min [tex]|| Ax − y||² + \||x|| ²/2, x.[/tex]
Therefore, we have demonstrated that the unique minimum-norm solution x* to the regularized least-squares problem is given by [tex]x* = (A A^T + λI)−1 A^T y.[/tex]
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Based on the scatterplot, select the most likely value of the linear correlation coefficient r. r=0 r = -0.5 r = 1 r = -1
Low-income students tend to have lower attendance rates and lower math test s
Based on the information provided, we cannot determine the most likely value of the linear correlation coefficient (r) solely based on the statement "Low-income students tend to have lower attendance rates and lower math test scores."
To determine the linear correlation coefficient, we would need to examine the scatterplot of the data that represents the relationship between the attendance rates and math test scores of low-income students. The scatterplot would show the pattern and direction of the relationship between these variables.
The value of the linear correlation coefficient (r) can range from -1 to 1. A positive value of r indicates a positive linear relationship, meaning that as one variable increases, the other tends to increase as well. A negative value of r indicates a negative linear relationship, meaning that as one variable increases, the other tends to decrease. A value of 0 indicates no linear relationship between the variables.
Without the scatterplot or any specific data points, we cannot determine the most likely value of r in this scenario. It is essential to analyze the scatterplot or have additional information about the relationship between attendance rates and math test scores to make an informed determination about the value of the linear correlation coefficient.
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In each of the following situations, explain what is wrong and why.
a. The null hypothesis H0: β3 = 0 in a multiple regression involving three explanatory variables implies there is no linear association between x3 and y.
b. The multiple correlation coefficient gives the average correlation between the response variable and each explanatory variable in the model.
a. The null hypothesis H0: β3 = 0 in a multiple regression does not imply there is no linear association between x3 and y; it suggests no statistically significant association. b. The multiple correlation coefficient (R-squared) measures the proportion of variance in the response variable explained by all explanatory variables, not the average correlation between the response variable and each explanatory variable.
a. The statement that the null hypothesis H0: β3 = 0 in a multiple regression involving three explanatory variables implies there is no linear association between x3 and y is incorrect. The null hypothesis H0: β3 = 0 actually implies that there is no statistically significant linear association between the specific explanatory variable x3 and the response variable y, holding all other variables constant in the multiple regression model. It does not necessarily mean that there is no linear association between x3 and y.
b. The statement that the multiple correlation coefficient gives the average correlation between the response variable and each explanatory variable in the model is incorrect. The multiple correlation coefficient, also known as the coefficient of multiple determination (R-squared), represents the proportion of the variance in the response variable that is explained by all the explanatory variables combined in the model. It measures the overall goodness-of-fit of the regression model but does not directly provide information about the individual correlations between the response variable and each explanatory variable separately. To assess the relationship between the response variable and each explanatory variable, you need to examine the individual coefficients (betas) or the partial correlation coefficients in the multiple regression model.
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A syllabus has the following weighted grade scale: 15% HW 60% Exams 25% Final The lowest exam from the class will be dropped. A student had the following scores: 100% HW 90% Exam 1, 86% Exam 2, 92% Exam 3, 84% Exam 4 78% Final. Calculate the final grade in the course.
To calculate the final grade in the course, we need to take into account the weighted grade scale and the fact that the lowest exam score will be dropped.
Let's break down the calculation step by step:
Calculate the average exam score after dropping the lowest score:
Exam 1: 90%
Exam 2: 86%
Exam 3: 92%
Exam 4: 84%
We drop the lowest score, which is Exam 2 (86%), and calculate the average of the remaining three exam scores:
Average exam score = (90% + 92% + 84%) / 3
= 88.67%
Calculate the weighted score for each category:
Homework (HW): 15% of the final grade
Exams (average of three exams): 60% of the final grade
Final Exam: 25% of the final grade
Weighted HW score = 100% * 15%
= 15%
Weighted Exam score = 88.67% * 60%
= 53.20%
Weighted Final Exam score = 78% * 25%
= 19.50%
Calculate the final grade:
Final Grade = Weighted HW score + Weighted Exam score + Weighted Final Exam score
Final Grade = 15% + 53.20% + 19.50%
= 87.70%
The final grade in the course, taking into account the weighted grade scale and dropping the lowest exam score, is 87.70%
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61 of the 856 digital video recorders (DVRs) in an inventory
are known to be defective. What is the probability that a randomly
selected item is defective? Express your answer as a percentage
ro
The probability that a randomly selected item is defective is 7.12%.
The given data can be represented in a tabular form as shown below:
Defective (D)Non-Defective (ND)
Total Sample Space (T)D61T856
Now, we need to calculate the probability that a randomly selected item is defective.
So, the probability that a randomly selected item is defective is given by:
P(D) = Number of Defective Items / Total Sample SpaceP(D)
= 61/856
Let's calculate the value of P(D) as follows:
P(D) = 61/856
= 0.0712
So, the probability that a randomly selected item is defective is 0.0712 or 7.12% (approximately)
Therefore, the probability that a randomly selected item is defective is 7.12%.
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I
sent this question from yesterday but nobody answered it.
Pleasee i need 13.3 answer only
479 13.1 Introduction: the importance of forecasting The role of forecasting is extremely important in the larward planning of any company Unfortunately it is never an exact wience as too many unknown
According to the given text, the topic discussed in the text is about the importance of forecasting. It states that forecasting plays a crucial role in the planning of any company.
However, it is not an exact science as there are too many unknown variables that can influence the forecasting process.
As a result, forecasts can only be seen as an approximation of what is to come. It is a means of assessing the future of a business, and it can help managers make more informed decisions based on the information available.
In business, forecasting is an essential tool that is used to estimate future trends, sales, and demand for products or services.
It allows companies to plan their resources more efficiently and effectively.
The importance of forecasting can be seen in various areas such as marketing, finance, and operations, among others. Forecasting helps companies make informed decisions, avoid surprises, and plan for future growth.
Summary:In conclusion, the given text is discussing the importance of forecasting in business planning. It highlights that forecasting is not an exact science as it is influenced by various unknown variables. However, forecasting is still important as it allows companies to plan their resources more efficiently and make informed decisions.
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You are testing the null hypothesis that there is no linear
relationship between two variables, X and Y. From your sample of
n=18, you determine that b1=5.3 and Sb1=1.4. What is the
value of tSTAT?
There is a statistically significant linear relationship between the variables X and Y.
To calculate the value of the t-statistic (tSTAT) for testing the null hypothesis that there is no linear relationship between two variables, X and Y, we need to use the following formula:
tSTAT = (b1 - 0) / Sb1
Where b1 represents the estimated coefficient of the linear regression model (also known as the slope), Sb1 represents the standard error of the estimated coefficient, and we are comparing b1 to zero since the null hypothesis assumes no linear relationship.
Given the information provided:
b1 = 5.3
Sb1 = 1.4
Now we can calculate the t-statistic:
tSTAT = (5.3 - 0) / 1.4
= 5.3 / 1.4
≈ 3.79
Rounded to two decimal places, the value of the t-statistic (tSTAT) is approximately 3.79.
The t-statistic measures the number of standard errors the estimated coefficient (b1) is away from the null hypothesis value (zero in this case). By comparing the calculated t-statistic to the critical values from the t-distribution table, we can determine if the estimated coefficient is statistically significant or not.
In this scenario, a t-statistic value of 3.79 indicates that the estimated coefficient (b1) is significantly different from zero. Therefore, we would reject the null hypothesis and conclude that there is a statistically significant linear relationship between the variables X and Y.
Please note that the t-statistic is commonly used in hypothesis testing for regression analysis to assess the significance of the estimated coefficients and the overall fit of the model.
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Consider the following description of data: Researchers at a large city hospital are investigating the impact of prenatal care on newborn health. They collected data from 785 births during 2011-2013. They kept track of the mother’s age, the number of weeks the pregnancy lasted, the type of birth (natural, C-section), the level of prenatal care the mother received (none, minimal, adequate), the birth weight of the baby, and the sex of the baby.
a) How many cases are involved with this study? (1 point)
b) Name three quantitative variables in this study and give their units of measure. If the units are not obvious from the description, give your best assumption. (3 points)
c) Name three qualitative variables in this study AND whether they’re ordinal or nominal. (3pts)
Type of birth (natural, C-section) - nominal variable
Level of prenatal care (none, minimal, adequate) - ordinal variable
Sex of the baby (male, female) - nominal variable
a) The study involves 785 cases.
b) Three quantitative variables in this study and their units of measure could be:
Mother's age - measured in years
Number of weeks the pregnancy lasted - measured in weeks
Birth weight of the baby - measured in grams or pounds
c) Three qualitative variables in this study could be:
Type of birth (natural, C-section) - nominal variable
Level of prenatal care (none, minimal, adequate) - ordinal variable
Sex of the baby (male, female) - nominal variable
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