Question

A 95% interval estimate of the mean cholesterol level among recent female Asian immigrants is (173.8, 194.2) milligrams/deciliter. The margin or error for this interval is,

10.2
9.8
9.2
8.8

Answer 1

Solution :

95% confidence interval = (173.8, 194.2) milligrams/deciliter

$\bar x$  = (Lower confidence interval + Upper confidence interval ) / 2

Sample mean = $\bar x$ = (173.8 + 194.2) / 2

Sample mean = $\bar x$ = 184

Margin of error = E = Upper confidence interval - $\bar x$

Margin of error = E = 194.2 - 184

Margin of error = E = 10.2