b) What is the probability that the clear height is less than 13 feet?
x < 13 feet
P(x < 13 | µ = 22 and = 4) = ?
= = 2.25
Probability value for z = 2.25 is 0.4878 = 0.5000 - 0.4878 = 0.0122.
c) What is the probability that the clear height is between 25 and 31 feet?
P(25 ≤ x ≤ 31 | µ = 22 and = 4) = ?
i) 0.75 = 0.2734 (from Table A.5)
ii) = 0.4878 (from Table A.5)
P = 0.4878 – 02734 = 0.2144