Question 1

$$\text { If } \hat { p } \text { is equal to } 0.88 \text {, then } \hat { q } \text { is equal to }$$________

Accepted Answer

A)  0.88 
B)  0.50 
C)  0.12 
D)  0.45 
A)  0.88 
B)  0.50 
C)  0.12 
D)  0.45

Question 2

A chi-square variable cannot be negative, and the distributions are positively skewed.

Accepted Answer

A) True 
 B)False

Question 3

The prices (in dollars) for a graphing calculator are shown below for 8 online vendors. Estimate the true mean price for this particular calculator with 95% confidence.
121 125 151 129
127 133 121 125

Accepted Answer

A)  $122.5 < \mu < 135.5$ 
B)  $116.9 < \mu < 141.1$ 
C)  $120.9 < \mu < 137.1$ 
D)  $126.1 < \mu < 131.9$ 
A)  $122.5 < \mu < 135.5$ 
B)  $116.9 < \mu < 141.1$ 
C)  $120.9 < \mu < 137.1$ 
D)  $126.1 < \mu < 131.9$

Question 4

Jennifer wants to find a 95% confidence interval for the time it takes her to get to work.
She kept records for 30 days and found her average time to commute to work was 20.5
minutes with a standard deviation for the population of 3.9 minutes. Jennifer's margin of
error would be 1.4 minutes.

Accepted Answer

A) True 
 B)False

Question 5

In order to find confidence intervals for variances and standard deviations, one
must assume that the variable is .

Accepted Answer

normally d

Question 6

A random sample of 50 voters found that 46% were going to vote for a certain candidate. Find the 95% limit for the population proportion of voters who will vote for that
Candidate.

Accepted Answer

A)  $34.4 \% < p < 57.6 \%$ 
B)  $32.2 \% < p < 59.8 \%$ 
C)  $39.1 \% < p < 52.9 \%$ 
D)  $33.3 \% < p < 58.7 \%$ 
A)  $34.4 \% < p < 57.6 \%$ 
B)  $32.2 \% < p < 59.8 \%$ 
C)  $39.1 \% < p < 52.9 \%$ 
D)  $33.3 \% < p < 58.7 \%$

Question 7

The confidence level of an interval estimate of a parameter is the probability that the
interval estimate will contain the parameter.

Accepted Answer

A) True 
 B)False

Question 8

The Pizza Shop wanted to determine what proportion of its customers ordered only cheese pizza. Out of 80 customers surveyed, 15 ordered only cheese pizza. What is the
99% confidence interval of the true proportion of customers who order only cheese
Pizza?

Accepted Answer

A)  $0.086 < p < 0.289$ 
B)  $0.115 < p < 0.260$ 
C)  $0.075 < p < 0.301$ 
D)  $0.102 < p < 0.273$ 
A)  $0.086 < p < 0.289$ 
B)  $0.115 < p < 0.260$ 
C)  $0.075 < p < 0.301$ 
D)  $0.102 < p < 0.273$

Question 9

Measurements were made of the milk fat content (in percent) in six brands of feta cheese variety of goat cheese), with the following results. Assume that the population is normally distributed.
$\begin{array}{llllll}
\hline 27.5 & 19.3 & 32.0 & 23.5 & 24.6 & 16.9 \
\hline
\end{array}$

Construct a $90 \%$ confidence interval for the population standard deviation $\sigma$.

Accepted Answer

A)  $3.44 < \sigma < 9.56$ 
B)  $3.77 < \sigma < 10.47$ 
C)  $3.67 < \sigma < 11.42$ 
D)  $4.02 < \sigma < 9.63$ 
A)  $3.44 < \sigma < 9.56$ 
B)  $3.77 < \sigma < 10.47$ 
C)  $3.67 < \sigma < 11.42$ 
D)  $4.02 < \sigma < 9.63$

Question 10

A population has a standard deviation $\sigma = 19.8$. How large a sample must be drawn so that a $99 \%$ confidence interval for $\mu$ will have a margin of error equal to $4.7 ?$

Accepted Answer

A)  215 
B)  118 
C)  7 
D)  11 
A)  215 
B)  118 
C)  7 
D)  11

Question 11

Find the 95% confidence interval for the standard deviation of the lengths of pipes if a sample of 11 pipes has a standard deviation of 10.6 inches.

Accepted Answer

A)  $54.9 < \sigma < 346.0$ 
B)  $7.6 < \sigma < 9.6$ 
C)  $7.4 < \sigma < 18.6$ 
D)  $101.4 < \sigma < 123.4$ 
A)  $54.9 < \sigma < 346.0$ 
B)  $7.6 < \sigma < 9.6$ 
C)  $7.4 < \sigma < 18.6$ 
D)  $101.4 < \sigma < 123.4$

Question 12

The rounding rule for a confidence interval for a proportion is to round off to three
decimal places.

Accepted Answer

A) True 
 B)False

Question 13

Find the critical value $t _ { \alpha / 2 }$ needed to construct a confidence interval of the given level with the given sample size.
Level $95 \%$, sample size 11

Accepted Answer

A)  1.960 
B)  2.228 
C)  1.812 
D)  2.201 
A)  1.960 
B)  2.228 
C)  1.812 
D)  2.201

Question 14

A study of elephants is conducted to determine the average weight of a certain subspecies of elephants. The standard deviation for the population is 500 pounds. At a
90% level, how many elephants need to be weighed so the average weight will be
Accurate to within 250 pounds?

Accepted Answer

A)  16 
B)  11 
C)  13 
D)  36 
A)  16 
B)  11 
C)  13 
D)  36

Question 15

$$\text { Find the critical value } z _ { \alpha / 2 } \text { needed to construct a(n) } 99.5 \% \text { confidence interval. }$$

Accepted Answer

A)  3.71 
B)  2.58 
C)  2.81 
D)  2.53 
A)  3.71 
B)  2.58 
C)  2.81 
D)  2.53

Question 16

The value for $\chi _ { \text {righ } } ^ { 2 }$
2 right for a $95 \%$ confidence interval when $n = 15$ is $26.119$.

Accepted Answer

A) True 
 B)False

Question 17

Find the level of the confidence interval that has the given critical value. 2.16

Accepted Answer

A)  98.46% 
B)  96.92% 
C)  3.08% 
D)  1.54% 
A)  98.46% 
B)  96.92% 
C)  3.08% 
D)  1.54%

Question 18

What is the value for $\chi ^ { 2 }$ for a $95 \%$ confidence interval when $n = 18$ ?

Accepted Answer

A)  8.231 
B)  8.672 
C)  7.564 
D)  9.390 
A)  8.231 
B)  8.672 
C)  7.564 
D)  9.390

Question 19

Find the margin of error for the given confidence level and values of $x$ and $n$. $x = 111 , n = 194$, confidence level $99 \%$

Accepted Answer

A)  0.428 
B)  0.572 
C)  r0.036 
D)  0.093 
A)  0.428 
B)  0.572 
C)  r0.036 
D)  0.093

Question 20

In a sample of 45 mice, a biologist found that 40% were able to run a maze in 30 seconds or less. Find the 95% limit for the population proportion of mice who can run a maze in
30 seconds or less.

Accepted Answer

A)  $25.7 \% < p < 54.3 \%$ 
B)  $28.0 \% < p < 52.0 \%$ 
C)  $18.5 \% < p < 61.5 \%$ 
D)  $32.8 \% < p < 47.2 \%$ 
A)  $25.7 \% < p < 54.3 \%$ 
B)  $28.0 \% < p < 52.0 \%$ 
C)  $18.5 \% < p < 61.5 \%$ 
D)  $32.8 \% < p < 47.2 \%$

$\text { If } \hat { p } \text { is equal to } 0.88 \text {, then } \hat { q } \text { is equal to }$ ________

A chi-square variable cannot be negative, and the distributions are positively skewed.

The prices (in dollars) for a graphing calculator are shown below for 8 online vendors. Estimate the true mean price for this particular calculator with 95% confidence. 121 125 151 129 127 133 121 125

Jennifer wants to find a 95% confidence interval for the time it takes her to get to work. She kept records for 30 days and found her average time to commute to work was 20.5 minutes with a standard deviation for the population of 3.9 minutes. Jennifer's margin of error would be 1.4 minutes.

In order to find confidence intervals for variances and standard deviations, one must assume that the variable is .

A random sample of 50 voters found that 46% were going to vote for a certain candidate. Find the 95% limit for the population proportion of voters who will vote for that Candidate.

The confidence level of an interval estimate of a parameter is the probability that the interval estimate will contain the parameter.

The Pizza Shop wanted to determine what proportion of its customers ordered only cheese pizza. Out of 80 customers surveyed, 15 ordered only cheese pizza. What is the 99% confidence interval of the true proportion of customers who order only cheese Pizza?

A population has a standard deviation $\sigma = 19.8$ . How large a sample must be drawn so that a $99 \%$ confidence interval for $\mu$ will have a margin of error equal to $4.7 ?$

Find the 95% confidence interval for the standard deviation of the lengths of pipes if a sample of 11 pipes has a standard deviation of 10.6 inches.

The rounding rule for a confidence interval for a proportion is to round off to three decimal places.

Find the critical value $t _ { \alpha / 2 }$ needed to construct a confidence interval of the given level with the given sample size. Level $95 \%$ , sample size 11

A study of elephants is conducted to determine the average weight of a certain subspecies of elephants. The standard deviation for the population is 500 pounds. At a 90% level, how many elephants need to be weighed so the average weight will be Accurate to within 250 pounds?

$\text { Find the critical value } z _ { \alpha / 2 } \text { needed to construct a(n) } 99.5 \% \text { confidence interval. }$

The value for $\chi _ { \text {righ } } ^ { 2 }$ 2 right for a $95 \%$ confidence interval when $n = 15$ is $26.119$ .

Find the level of the confidence interval that has the given critical value. 2.16

What is the value for $\chi ^ { 2 }$ for a $95 \%$ confidence interval when $n = 18$ ?

Find the margin of error for the given confidence level and values of $x$ and $n$ . $x = 111 , n = 194$ , confidence level $99 \%$

In a sample of 45 mice, a biologist found that 40% were able to run a maze in 30 seconds or less. Find the 95% limit for the population proportion of mice who can run a maze in 30 seconds or less.

The Nature of Probability and Statistics

Frequency Distributions and Graphs

Data Description

Probability and Counting Rules

Discrete Probability Distributions

The Normal Distribution

Hypothesis Testing

Testing the Difference Between Two Means, Two Variances, and Two Proportions

Correlation and Regression

Other Chi-Square Tests

Analysis of Variance

Nonparametric Statistics

Sampling and Simulation

Filters

Exam 7: Confidence Intervals and Sample Size

If p^ is equal to 0.88, then q^ is equal to \text { If } \hat { p } \text { is equal to } 0.88 \text {, then } \hat { q } \text { is equal to } If p^​ is equal to 0.88, then q^​ is equal to ________

A chi-square variable cannot be negative, and the distributions are positively skewed.

The prices (in dollars) for a graphing calculator are shown below for 8 online vendors. Estimate the true mean price for this particular calculator with 95% confidence. 121 125 151 129 127 133 121 125

Jennifer wants to find a 95% confidence interval for the time it takes her to get to work. She kept records for 30 days and found her average time to commute to work was 20.5 minutes with a standard deviation for the population of 3.9 minutes. Jennifer's margin of error would be 1.4 minutes.

In order to find confidence intervals for variances and standard deviations, one must assume that the variable is .

A random sample of 50 voters found that 46% were going to vote for a certain candidate. Find the 95% limit for the population proportion of voters who will vote for that Candidate.

The confidence level of an interval estimate of a parameter is the probability that the interval estimate will contain the parameter.

The Pizza Shop wanted to determine what proportion of its customers ordered only cheese pizza. Out of 80 customers surveyed, 15 ordered only cheese pizza. What is the 99% confidence interval of the true proportion of customers who order only cheese Pizza?

A population has a standard deviation σ=19.8\sigma = 19.8σ=19.8 . How large a sample must be drawn so that a 99%99 \%99% confidence interval for μ\muμ will have a margin of error equal to 4.7?4.7 ?4.7?

Find the 95% confidence interval for the standard deviation of the lengths of pipes if a sample of 11 pipes has a standard deviation of 10.6 inches.

The rounding rule for a confidence interval for a proportion is to round off to three decimal places.

Find the critical value tα/2t _ { \alpha / 2 }tα/2​ needed to construct a confidence interval of the given level with the given sample size. Level 95%95 \%95% , sample size 11

A study of elephants is conducted to determine the average weight of a certain subspecies of elephants. The standard deviation for the population is 500 pounds. At a 90% level, how many elephants need to be weighed so the average weight will be Accurate to within 250 pounds?

Find the critical value zα/2 needed to construct a(n) 99.5% confidence interval. \text { Find the critical value } z _ { \alpha / 2 } \text { needed to construct a(n) } 99.5 \% \text { confidence interval. } Find the critical value zα/2​ needed to construct a(n) 99.5% confidence interval.

The value for χrigh 2\chi _ { \text {righ } } ^ { 2 }χrigh 2​ 2 right for a 95%95 \%95% confidence interval when n=15n = 15n=15 is 26.11926.11926.119 .

Find the level of the confidence interval that has the given critical value. 2.16

What is the value for χ2\chi ^ { 2 }χ2 for a 95%95 \%95% confidence interval when n=18n = 18n=18 ?

Find the margin of error for the given confidence level and values of xxx and nnn . x=111,n=194x = 111 , n = 194x=111,n=194 , confidence level 99%99 \%99%

In a sample of 45 mice, a biologist found that 40% were able to run a maze in 30 seconds or less. Find the 95% limit for the population proportion of mice who can run a maze in 30 seconds or less.

The Nature of Probability and Statistics

Frequency Distributions and Graphs

Data Description

Probability and Counting Rules

Discrete Probability Distributions

The Normal Distribution

Hypothesis Testing

Testing the Difference Between Two Means, Two Variances, and Two Proportions

Correlation and Regression

Other Chi-Square Tests

Analysis of Variance

Nonparametric Statistics

Sampling and Simulation

Filters

$\text { If } \hat { p } \text { is equal to } 0.88 \text {, then } \hat { q } \text { is equal to }$ ________

A population has a standard deviation $\sigma = 19.8$ . How large a sample must be drawn so that a $99 \%$ confidence interval for $\mu$ will have a margin of error equal to $4.7 ?$

Find the critical value $t _ { \alpha / 2 }$ needed to construct a confidence interval of the given level with the given sample size. Level $95 \%$ , sample size 11

$\text { Find the critical value } z _ { \alpha / 2 } \text { needed to construct a(n) } 99.5 \% \text { confidence interval. }$

The value for $\chi _ { \text {righ } } ^ { 2 }$ 2 right for a $95 \%$ confidence interval when $n = 15$ is $26.119$ .

What is the value for $\chi ^ { 2 }$ for a $95 \%$ confidence interval when $n = 18$ ?

Find the margin of error for the given confidence level and values of $x$ and $n$ . $x = 111 , n = 194$ , confidence level $99 \%$