Question

15. Assume that the heights of men are normally distributed with a mean of 70 inches and a standard deviation of 3.5 inches. If 100 men are randomly​ selected, find the probability that they have a mean height greater than 71 inches. A. 9.9671

Answer 1

Mean, = 70 in

Standard deviation, = 3.5 in

Sample size, n = 100

For sampling distribution of mean, P( < A) = P(Z < )/)

= = 70 in

=

= 0.35 in

P(mean height greater than 71 inches) = P( > 71)

= 1 - P( < 71)

= 1 - P(Z < (71 - 70)/0.35)

= 1 - P(Z < 2.86)

= 1 - 0.9979

= 0.0021