Question

The proportion of drivers who use seat belts depends on things like age, gender, ethnicity, and local law.

As part of a broader study, investigators observed a random sample of 117 female Hispanic drivers in

Boston; 68 of these drivers were wearing seat belts.

Do the data give good reason to conclude that more than half of Hispanic female drivers in Boston wear

seat belts? To test this claim, answer each of the following questions.

a.

State the null and alternative hypotheses

b.

Compute the test statistic.

c.

Calculate the P-value.

d.

State your conclusion in the context of the problem at the



= 0.05 level of significance.

e.

Give the plus four 95% confidence interval for the proportion of all female Hispanic drivers in

Boston who wear seat belts.

f.

Write a sentence to interpret the interval you found in part a in the context of the problem.

Answer 1

Solution:

a) The null and alternative hypotheses are:

b) The test statistic is:

Where:

c. The p-value is:

d. Reject the null hypothesis at 0.05 significance level

e. The 95% confidence interval is:

e. Since most of the values confidence interval is above 0.50, we, therefore, support the claim