Question

A survey is administered to 57 faculty members at GCC asking how long they have been teaching in their field. The average response from this sample was 13.2 years and the sample standard deviation was 4.8 years. Find a 98% confidence interval estimate for the average number of years all GCC faculty members have been teaching in their field.

Answer 1

Solution :

Given that,

t /2,df = 2.395

Margin of error = E = t/2,df * (s /n)

= 2.395 * (4.8 / 57)

Margin of error = E = 1.5

The 98% confidence interval estimate of the population mean is,

- E < < + E

13.2 - 1.5 < < 13.2 + 1.5

11.7 < < 14.7

(11.7 , 14.7)