Question 1

In a random sample of 892 college students in the United States, 272 say they skip at least one

class per week.

Find the point estimate for the proportion parameter for this population. Write your answer as a

decimal rounded to three decimal places.

0.305

0.695

0.272

0.50

Question 2

A survey of 6000 adults found that 58% say that they would take a ride in a fully self-driving car.

A normal distribution may be used to model the sample proportion. At 95% confidence, the

margin of error for this estimate was 2.4%. Find the 95% confidence interval of the true

proportion who said that they would take a ride in a self-driving car.

Source: World Economic Forum and Boston Consulting Group.

(0.568, 0.592)

(0.556, 0.604)

(0.556, 0.568)

(0.592, 0.604)

Question 3

A survey of 6000 adults found that 58% say that they would take a ride in a fully self-driving car.

The standard error for this estimate was 1.2%, and a normal distribution may be used to model

the sample proportion.

True or False: According to the Central Limit Theorem on Success-Failure, the sampling

distribution would be approximately normal.

Source: World Economic Forum and Boston Consulting Group.

True

False

Question 4

It has been reported that one in four medical doctors received their degrees from foreign

schools. A hospital researcher believes that the percentage is less than 25%. Write the null

hypothesis for this situation.

Ho : p = 0.25

Ho : p LaTeX: e

0.25

Ho : p < 0.25

Ho : p = 0.75

Question 5

If a given value (for example, the null hypothesized value of a parameter) is within a 99%

confidence interval, it will also be within a 95% confidence interval.

True

False

Question 6

A comprehensive survey released by a college reports that the true proportion of all students at

the college who use drugs is 0.3. You randomly survey 100 students in your dorm and record

that the proportion of students who use drugs is 0.15. The proportion of all students at this

college who use drugs is a __?__ and the proportion of students who use drugs in your dorm is a

__?__.

parameter; statistic

statistic; parameter

population; sample

measure of central tendency, measure of variability

none of the above

Question 7

Approximately 19% of physics majors in the US are women. To test whether your college differs

significantly from this national average, you take a random sample of 50 physics majors at your

college and find that 11 are female. Calculate the standard error for this situation. Round to four

decimal places.

0.0586

0.0034

0.0036

0.0601

0.5000

Question 8

Approximately 19% of physics majors in the US are women. To test whether your college differs

signicantly from this national average, you take a random sample of 50 physics majors at your

college and find that 11 are female. Calculate the appropriate test statistic to determine whether

your college differs signicantly from the national rate.

0.51

0.54

0.48

-0.51

-0.54

Question 9

The World Bank reports that 1.7% of the US population lives on less than $2 per day. A policy

maker claims that this number is misleading because of variation from state to state and rural to

urban. To investigate this, she takes a random sample of 100 households in Atlanta to compare

with the national average and finds that 2.1% of the Atlanta population live on less than $2/day.

Select the null and alternative hypothesis to test whether Atlanta differs significantly from the

national percentage.

Ho: p LaTeX: e

0.021; Ha: p = 0.021

H0: p LaTeX: e

0.017, Ha: p = 0.017

Ho: p = 0.017, Ha: p LaTeX: e

0.017

H0: LaTeX: \mu

= 0.021, Ha: LaTeX: \mu LaTeX: e

0.021

Ho: LaTeX: \mu = 2, Ha: LaTeX: \mu e

2

Question 10

Complete the following sentence: When conducting a hypothesis test, we __?__ and then

evaluate the test results to determine if there is enough evidence to __?__ .

Assume that the null hypothesis is true; reject the null hypothesis

Assume that the null hypothesis is false; accept the null hypothesis

Assume that the alternative hypothesis is true; reject the null hypothesis

Assume the alternative hypothesis is false; reject the alternative hypothesis

Question 11

When testing a hypothesis at a level of significance of 0.05, we end up with a p-value of 0.043.

Determine the conclusion.

Reject the null hypothesis

Fail to reject the null hypothesis

Accept the null hypothesis

Accept the alternative hypothesis

Question 12

A Type I error occurs when we fail to reject the null hypothesis when it is false.

True

False

Question 13

When working with Confidence Intervals of a single proportion we use a z-value of __________

for a 95% confidence level.

1.96

2.58

1.575

0.05

Question 14

In a hypothesis testing of a particular claim that the proportion of teenagers who like to read is

36%, we find the confidence interval of a sample to be (0.31, 0.38). In using the confidence

interval to make a decision, we determine which of the following:

Fail to reject null hypothesis since the claim is within the confidence interval

Reject the null hypothesis since the claim is within the confidence interval

Further research needs to be done.

Determine the p-value because there is not enough information.

Question 15

The null hypothesis will also contain an equality statement in the claim.

True

False