Question

You own a small storefront retail business and are interested in determining the average amount of money a typical customer spends per visit to your store. You take a random sample over the course of a month for 11 customers and find that the average dollar amount spent per transaction per customer is $114.645 with a standard deviation of $18.2388. Create a 90% confidence interval for the true average spent for all customers per transaction.

Question 6 options:

	1) ( 109.146 , 120.144 )
	2) ( 112.833 , 116.457 )
	3) ( -104.678 , 124.612 )
	4) ( 104.768 , 124.522 )
	5) ( 104.678 , 124.612 )

Question 7 (1 point)

You read an article in Golf Digest that someone with your average drive distance will have an average score of 75.76. You keep track of your scores for the next 13 rounds and see that your average score is 83.11 with a standard deviation of 2.036 strokes. You create a 95% confidence interval for your average score and it is (81.88, 84.34). Given this information, what is the best conclusion?

Question 7 options:

	1) The percentage of rounds in which you score more than 75.76 is 95%.
	2) The average score does not significantly differ from 75.76.
	3) We cannot determine the proper interpretation based on the information given.
	4) We are 95% confident that your average score is greater than 75.76.
	5) We are 95% confident that your average score is less than 75.76.

Question 8 (1 point)

It is believed that using a solid state drive (SSD) in a computer results in faster boot times when compared to a computer with a traditional hard disk (HDD). You sample a group of computers and use the sample statistics to calculate a 99% confidence interval of (3.05, 10.94). This interval estimates the difference of (average boot time (HDD) - average boot time (SSD)). What can we conclude from this interval?

Question 8 options:

	1) There is no significant difference between the average boot time for a computer with an SSD drive and one with an HDD drive at 99% confidence.
	2) We are 99% confident that the average boot time of all computers with an SSD is greater than the average of all computers with an HDD.
	3) We are 99% confident that the difference between the two sample means falls within the interval.
	4) We do not have enough information to make a conclusion.
	5) We are 99% confident that the average boot time of all computers with an HDD is greater than the average of all computers with an SSD.

Question 9 (1 point)

The owner of a golf course wants to determine if his golf course is more difficult than the one his friend owns. He has 11 golfers play a round of 18 holes on his golf course and records their scores. Later that week, he has the same 11 golfers play a round of golf on his friend's course and records their scores again. The average difference in the scores (treated as the scores on his course - the scores on his friend's course) is 7.274 and the standard deviation of the differences is 12.3106. Calculate a 95% confidence interval to estimate the average difference in scores between the two courses.

Question 9 options:

	1) (0.9964, 15.5444)
	2) (3.5622, 10.9858)
	3) (-0.8956, 15.4436)
	4) (5.0459, 9.5021)
	5) (-0.9964, 15.5444)

Answer 1