# Question: A confidence interval for the difference between the means of

A confidence interval for the difference between the means of two normally distributed populations based on the following dependent samples is desired:

Before After

6 ............ 8

12 ................ 14

8 ............ 9

10 ................ 13

6 ................. 7

a. Find the margin of error for a 90% confidence level.

b. Find the UCL and the LCL for a 90% confidence level.

c. Find the width of a 95% confidence interval.

Before After

6 ............ 8

12 ................ 14

8 ............ 9

10 ................ 13

6 ................. 7

a. Find the margin of error for a 90% confidence level.

b. Find the UCL and the LCL for a 90% confidence level.

c. Find the width of a 95% confidence interval.

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