Question

The ratio of Ed’s cars to Pete’s cars was 5:2 at first. After Ed gave 30 cars to Pete, they had an equal amount of cars each. How many cars did they have altogether?

Answer 1

140

Explanation:

Answer 2

The number of "ratio units" differs by 3. If 1.5 is subtracted from the high number and the same value added to the low number, the ratio would be 3.5:3.5, or 1:1. We conclude that 1.5 "ratio units" corresponds to 30 cars, so each "ratio unit" represents 20 cars.

The two have a total of 5+2 = 7 "ratio units" so have a total of 140 cars.