Question

In the country of United States of Heightlandia, the height measurements of ten-year-old children are approximately normally distributed with a mean of 55.4 inches, and standard deviation of 4.1 inches.

A) What is the probability that a randomly chosen child has a height of less than 61.25 inches?

Answer= (Round your answer to 4 decimal places.)

B) What is the probability that a randomly chosen child has a height of more than 46.5 inches?

Answer= (Round your answer to 4 decimal places.)

Answer 1

(A)

P(X < 61.25) = P((X - 55.4)/4.1 < (61.25 - 55.4)/4.1)

… ≈ P(Z ≤ 0.1427)

… ≈ 0.5567

(B)

P(X > 46.5) = P((X - 55.4)/4.1 > (46.5 - 55.4)/4.1)

… ≈ P(Z > -2.1707)

… ≈ 1 - P(Z ≤ -2.1707)

… ≈ 0.9850