A certain car gets 20 miles per gallon when driven in the city and 30

A certain car gets 20 miles per gallon when driven in the city and 30 miles per gallon when driven on the highway. On a certain day the car was driven 500 miles in the city and on the highway and it consumed 20 gallons of gas. How many miles did the car travel on the highway that day? A. 150 B. (…)