Question

For a sample group of 22, the mean is 86 with a standard deviation of 5. What is the 90% confidence interval of the true mean of the sample? Can you please explain the steps you used to get the answer. Thanks.

Answer 1

Formula:

CI90 = mean + or - 1.645(sd/√n)

Substituting your data:

CI90 = 86 + or - 1.645(5/√22)

Finish the calculations for your confidence interval.

Answer 2

Thank you so much!