Afamily has two cars. during one particular week, the first car consumed 25 gallons of gas and the second consumed 40 gallons of gas. the two cars drove a combined total of 1225 miles, and the sum of their fuel efficiencies was 40 miles per gallon. what were the fuel efficiencies of each of the cars that week?
first car: ~ miles per gallon
second car: ~ miles per gallon

Step-by-step explanation:

Let x represent the fuel efficiency of the car that used the most gas. Since the sum of the fuel efficiencies is 40 mpg, the other car had a fuel efficiency of (40-x). Then the combined miles driven is ...

  40x +25(40-x) = 1225

  15x = 225

  x = 15

  (40-x) = 25

The first car got 25 miles per gallon; the second car got 15 miles per gallon.

We made use of the relation ...

  gallons × (miles/gallon) = miles