Question

(18.12) Example 16.1 assumed that the body mass index (BMI) of
all American young women follows a Normal distribution with
standard deviation ? = 7.5.

How large a sample would be needed to estimate the mean BMI ? in
this population to within ±1 with 95% confidence?

Give your answer as a whole number.

Fill in the blank:

Answer #1

Population standard deviation =7.5

Margin of error =E=1

Level of significance = 1-0.95=0.05

Z critical value is (by using Z table)=
1.96

Sample size formula is

=216.09

Assumed that the body mass index(BMI) of all American young
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