A researcher conducts a mileage economy test involving 80 cars. The frequency distribution describing average miles per gallon (mpg) appears in the following table.

a. Construct the relative frequency distribution. What proportion of the cars got at least 20 mpg but less than 25 mpg? What proportion of the cars got less than 35 mpg? What proportion of the cars got 35 mpg or more? 

b. Construct a histogram. Comment on the shape of the distribution.

Transcribed Image Text:

Average mpg 15 < x < 20 20 < x < 25 25 < x < 30 30 < x < 35 35 < x < 40 40 < x < 45 Frequency 15 30 15 10 7 3