μ=42
σ=1.5
so
Z(38)=(38-μ)/σ
Look up a normal distribution table for the probability of exceedingZ(38), which is the same as the probability of not exceeding -Z(38).
Post your answer for checking if you wish.
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.
3 answers
.9961
.0039 or 39%