Question

The weights of 1,000 men in a certain town follow a normal distribution with a mean of 150 pounds and a standard deviation of 15 pounds.

From the data, we can conclude that the number of men weighing more than 165 pounds is about , and the number of men weighing less than 135 pounds is about .

Answer 1

z = ( 135 - μ ) / σ = -1
z = ( 165 - μ ) / σ = 1
P (x < 135) = P (z < -1) = 0.1587
P (165 < x) = P (1 < z) = 0.1587
.187 * 1000 = 187 more than 165
.187 * 1000 = 187 less than 135