This assignment is due at 11:59 pm (Beijing time) on the date listed on Moodle but you should work on it throughout the week as you finish each Section (the questions are labeled by Section number). Write all work on separate paper,scan, and submit the assignment to Moodle. Be sure to show all steps for full credit.

1. Section 9.1

In a study of Burger King drive-through orders, it was found that 264 orders were accurate and 54 were not

accurate. For McDonald’s, 329 orders were found to be accurate while 33 were not. Use a 0.05 significance level to test the claim that the Burger King and McDonald’s have the same accuracy rates.

(a) Test the claim using a hypothesis test.

(b) Test the claim by constructing the appropriate confidence interval.

2. Section 9.2

A group of 40 nonsmokers was exposed to second-hand smoke and their cotinine levels (a product of nicotine) had amean of 60.58 ng/mL and a standard deviation of 138.08 ng/mL. Another group of 40 nonsmokers was not

exposed to second-hand smoke and their cotinine levels had a mean of 16.35 ng/mL and a standard deviation of 62.53 ng/mL.

(a) Use a 0.05 significance level to test the claim that nonsmokers exposed to second-hand smoke have a

higher mean cotinine level than nonsmokers not exposed to second-hand smoke.

(b) Construct the appropriate confidence interval for the hypothesis test in part (a)

3. Section 9.3

As part of a national survey, the Department of Health and Human Services obtained self-reported heights (inches) and measured heights (inches) for males aged 12 – 16. Listed below are sample results from the survey. Construct  a 99% Confidence Interval estimate of the mean difference between reported heights and measured heights.

Interpret the resulting confidence interval.