Question

The Environmental Protection Agency

measures a mean gas mileage for recently tested cars as 24.8 mpg with a standard

deviation of 6.2 mpg. The dataset

on Fuel economy in StatCrunch gives an average of

24.2 mpg with a standard deviation of 6.5 mpg. Joe’s car is estimated at 30 mpg.

(a) Calculate the z-scores to find the relative tab at both sources (the Exercise and

the Dataset).

(b) Relative to the other cars,

with which source will Joe have

the highest mpg?

These next questions focus on the

Dataset. Assume a normal model and use the

calculator functions normalcdf and InvNorm.

(c) What percent of cars had a measure of less than 20 mpg?

(d) What percent of cars had a

measure of more than 30 mpg?

Answer 1