Question

Given two independent random samples with the following results:

n1=7

x‾1=129

s1=14

n2=14    

x‾2=159

s2=24

Use this data to find the 95% confidence interval for the true difference between the population means. Assume that the population variances are not equal and that the two populations are normally distributed.

Step 1 of 3:

Find the point estimate that should be used in constructing the confidence interval.

Step 2 of 3:

Find the margin of error to be used in constructing the confidence interval. Round your answer to six decimal places.

Step 3 of 3:

Construct the 95% confidence interval. Round your answers to the nearest whole number.

Answer 1

Part 1)

Part 2)

Margin of Error =   = 17.470274

Part 3)

Confidence interval :-

t(α/2, DF) = t(0.05 /2, 18 ) = 2.101

Lower Limit =
Lower Limit = -47.4703 ≈ - 47
Upper Limit =
Upper Limit = -12.5297 ≈ - 13
95% Confidence interval is ( -47 , -13 )