Question

The true highway mileage, Y, of a specific brand of hybrid vehicle has a normal distribution with a mean of 42 and a standard deviation of 1.5. Find the probability that a randomly selected hybrid vehicle gets more than 38 miles to the gallon.

Answer 1

μ=42
σ=1.5
so
Z(38)=(38-μ)/σ
Look up a normal distribution table for the probability of <i>exceeding</i>Z(38), which is the same as the probability of <i>not</i> exceeding -Z(38).

Post your answer for checking if you wish.

Answer 2

.9961

Answer 3

.0039 or 39%