Question

Outlet Deluxe Standard
1 39 27
2 39 28
3 45 35
4 38 30
5 40 30
6 39 34
7 35 29

here is the data found in problem 3 to answer question 9

QUESTION 7

A manufacture produces both deluxe and standard models of an automatic sander designed for home use. Selling prices obtained from a sample of retail outlets can be found in the "Problem 3" tab. Formulate the hypothesis test to determine if the mean difference between the prices is $7.
QUESTION 9

Determine the 95% confidence interval for the data in problem 7.
      
[2.47, 15.24]
      
[1.47, 16.24]
      
[3.47, 14.24]

only answer question 9 and choose one of the given answers , i already inputed 1.47, 16.24 as an asnwer and it is incorrect, so its either 2.47, 15.24 or 3.47, 14.24 please show your work and circle the final answer above is all the information and data needed to answer question 9

Answer 1

Since here we are interested in the difference values, so we first calculate the difference for each pair, as follows:

Difference = Deluxe-Standard

The values obtained using the above formula are:

12, 11, 10, 8, 10, 5, 6

For this data the descriptive statistics is:

Mean m = 8.86

Standard deviation S = 2.61

Sample size n = 7

Standard error, S' = S/(n^0.5) = 2.61/(7^0.5) = 0.986

The 95% CI is:

(m-7)-(1.96*S') < mean difference d < (m-7)+(1.96*S')

(8.86-7)-(1.96*0.986) < d < (8.86-7)+(1.96*0.986)

-0.072 < d < 3.79

So the answer should be none of the given options.