Question

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 10 cars, the average wait time is 7.21 minutes with a standard deviation of 1.6012 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)	( 5.605 , 8.815 )

2)	( 6.704 , 7.716 )

3)	( 5.564 , 8.856 )

4)	( -5.564 , 8.856 )

5)	( 3.96 , 10.46 )

Question 2 (1 point)

The owner of a local golf course wanted to determine the average age (in years) of the golfers that played on the course. In a random sample of 27 golfers that visited his course, the sample mean was 37.3 years old and the standard deviation was 6.95 years. Using this information, the owner calculated the confidence interval of (33.6, 41) with a confidence level of 99% for the average age. Which of the following is an appropriate interpretation of this confidence interval?

Question 2 options:

1)	We are 99% confident that the proportion of the ages of all golfers is between 33.6 and 41 years old.

2)	We are certain that 99% of the average ages of all golfers will be between 33.6 and 41 years old.

3)	We are 99% confident that the average age of the golfers surveyed is between 33.6 and 41 years old.

4)	We cannot determine the proper interpretation of this interval.

5)	We are 99% confident that the average age of all golfers that play on the golf course is between 33.6 and 41 years old.

Question 3 (1 point)

The owner of a local golf course wants to estimate the difference between the average ages of males and females that play on the golf course. He samples a group of men and women and then uses the sample statistics to calculate a 95% confidence interval of (3.71, 19.29). This interval estimates the difference of (the average age of men - the average age of women). What can we conclude from this interval?

Question 3 options:

1)	We do not have enough information to make a conclusion.

2)	We are 95% confident that the average age of all men who play at the course is greater than the average age of all women.

3)	We are 95% confident that the average age of all women who play at the course is greater than the average age of men.

4)	We are 95% confident that the difference between the two sample means falls within the interval.

5)	There is no significant difference between the average age of men and women that play at the course at 95% confidence.

Answer 1