Question

The mean number of hours of study time per week for a sample of 554 students is 22. If the margin of error for the population mean with a 95% confidence interval is 2.1, construct a 95% confidence interval for the mean number of hours of study time per week for all students.

Answer #1

Solution

Given that,

sample mean = = 22

Margin of error = E = 2.1

The 95% confidence interval estimate of the population mean is,

- E < < + E

22 - 2.1 < < 22 + 2.1

19.9 < < 24.1

(19.9 , 24.1)

A 95% confidence interval for the mean number of hours of study time per week for all students is : (19.9 , 24.1)

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