Question

The mean number of hours of study time per week for a sample of 524 high-school students is 27. If the margin of error for the population mean with a 98% confidence interval is 1.7, construct a 98% confidence interval for the mean number of hours of study time per week for all high-school students.

Lower endpoint?

upper endpoint?

Answer 1

Solution :

Given that,

Point estimate = sample mean = $\bar x$ = 27

Margin of error = E = 1.7

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

$\bar x$ - E < $\mu$ < $\bar x$ + E

27 - 1.7 < $\mu$ < 27 + 1.7

25.3 < $\mu$ < 28.7

Lower endpoint = 25.3

Upper endpoint = 28.7