A tune-up increases a car’s fuel efficiency by 5%. If a car averaged 20 miles per gallon before the tune-up, how many miles per gallon will it average after the tune-up?

A tune-up increases a car’s fuel efficiency by 5%. If a car averaged 20 miles per gallon before the tune-up, how many miles per gallon will it average after the tune-up?

Detailed Explanation

Multiply 20 × 0.05 to determine how many more miles per gallon the car will get. The answer is 1.

Then add the number of additional miles per gallon the car will get to the original number of miles per gallon the car gets to reach the new average: 1 + 20 = 21.

Then add the number of additional miles per gallon the car will get to the original number of miles per gallon the car gets to reach the new average: 1 + 20 = 21.