Suppose the number of equipment sales and service contracts that a store sold during the last six months for treadmills and exercise bikes was as follows:

 Suppose the number of equipment sales and  service contracts that a store sold during the last six months for  treadmills and exercise bikes was as follows: 

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:

1. Construct a 95 percent confidence interval for the difference  between the proportions of service contracts sold on treadmills versus  exercise bikes.
2. Is there a major difference between the two pieces of equipment? Why or why not?