Question

Heights of American adult women are normally distributed with mean 63.6 inches and standard deviation 2.5 inches. Find the height of an adult woman that corresponds to the 80th percentile.

Answer 1

65.7

Explanation:

Given ;

Mean, m = 63.6

Standard deviation, s = 2.5

80th percentile = 80 / 100 = 0.8

The Zscore corresponding to the 80th percentile ; Z < P = 0.842 (Z probability calculator)

Zscore = (x - m) / s

0.842 = (x - 63.6) / 2.5

0.842 * 2.5 = x - 63.6

2.105 = x - 63.6

x = 63.6 + 2.105

x = 65.705