Question

Question 1 (1 point)

Suppose you are a civil engineer, specializing in traffic volume control for the City of Grand Rapids. Your department has been receiving a multitude of complaints about traffic wait times for a certain intersection in the heart of downtown. To see if these claims are valid, you want to monitor the true average wait time at that intersection. Over the course of a few months, you record the average number of minutes a car waits at the intersection between 4:00 PM and 5:00 PM. With a sample size of 14 cars, the average wait time is 6.476 minutes with a standard deviation of 1.6154 minutes. Construct a 99% confidence interval for the true average wait time for a car at the intersection between 4:00 PM and 5:00 PM.

Question 1 options:

	1) ( 5.175 , 7.777 )
	2) ( -5.175 , 7.777 )
	3) ( 5.191 , 7.761 )
	4) ( 3.464 , 9.488 )
	5) ( 6.044 , 6.908 )

Question 2 (1 point)

In a climate survey, it was determined that in a random sample of 19 days, the average temperature in Kalamazoo at 2:00 PM in the months of July and August is 73.41 degrees with a standard deviation of 3.142 degrees. Using this information, a 99% confidence interval for the average is (71.34, 75.48). Which of the following is the appropriate interpretation of this interval?

Question 2 options:

	1) We are 99% confident that the average daily temperature for the months of July and August at 2:00 PM for the days recorded is between 71.34 and 75.48.
	2) We are 99% confident that the proportion of all days' temperatures will fall between 71.34 and 75.48.
	3) We cannot determine the proper interpretation of this interval.
	4) We are 99% confident that the average daily temperature for the months of July and August at 2:00 PM is between 71.34 and 75.48.
	5) We are certain that 99% of the days in the months of August and July will have a temperature at 2:00 PM between 71.34 and 75.48.

Question 3 (1 point)

Not all Walmart stores carry the same merchandise. In fact, in an audit of 1665 random stores, only 521 carried snowsuits seasonally. What is the 99% confidence interval estimate for the total number of Walmart stores that carry snowsuits?

Question 3 options:

	1) ( 0.65782 , 0.71636 )
	2) ( 0.28648 , 0.33935 )
	3) ( 0.30155 , 0.32428 )
	4) ( 0.28364 , 0.34218 )
	5) ( -0.28364 , 0.34218 )

Question 4 (1 point)

You work for a pharmaceutical company that is testing a new cholesterol drug. The proportion of patients on the previous drug who had a positive treatment was 0.329. You want to see if the new drug is more effective than the previous drug. You conduct a sample of 99 patients on the new drug and find that 59 have had a positive treatment effect. The 99% confidence interval is ( 0.4689 , 0.723 ). What is the best conclusion you can make of those listed below?

Question 4 options:

	1) We can not conclude that the proportion of patients who see a positive treatment effect with the new drug differs from 0.329.
	2) We can claim that the proportion of patients who see a positive treatment effect with the new drug is smaller than 0.329.
	3) The confidence interval does not provide enough information to form a conclusion.
	4) The proportion of patients on the new drug who saw a positive treatment effect from 0.329 is 99%.
	5) We can claim that the proportion of patients who see a positive treatment effect with the new drug is larger than 0.329.

Answer 1