Homework Assignment 6 – MAT510
Suppose the number of equipment sales and service contracts that a store sold during the last six (6) months for treadmills and exercise bikes was as follows:
Treadmill Exercise Bike
Total sold 185 123
Service contracts 67 55
The store can only sell a service contract on a new piece of equipment. Of the 185 treadmills sold, 67 included a service contract and 118 did not.
Complete the following questions in the space provided below:
Construct a 95 percent confidence interval for the difference between the proportions of service contracts sold on treadmills versus exercise bikes.
Is there a major difference between the two pieces of equipment? Why or why not?
Solution Preview
Confidence
Q1
T1 = number of service contracts for sold treadmills
T2 = number of service contracts for sold Exercise Bikes
T1 = 67/185
T1 = 0.362162
T2 = 55/123
T2 = 0.447154
T=n1t1 +n2t2/ n1 + N2
(269 words)