Question

A family has two cars. The first car has a fuel efficiency of 35 miles per gallon of gas and the second has a fuel efficiency of 40 miles per gallon

of gas. During one particular week, the two cars went a combined total of 2475 miles, for a total gas consumption of 65 gallons. How many
gallons were consumed by each of the two cars that week?
First car: ___ gallons
Second car:___ gallons

Answer 1

first car: 25 gallons

second car: 40 gallons

Explanation:

1) 35 miles/gallon consumption=distance/volume

2) 40 miles/gallon distance=consumption*volume

2475 miles = d1 + d2

= 35*v1 + 40*v2

v1 + v2 = 65

v2 = 65 - v1

2475 = 35*v1 + 40*(65 - v1)

2475 = 35*v1 + 2600 - 40*v1 /-2600

-125 = -5*v1

v1 = 25 gallons

v2 = 65 - v1

v2 = 40 gallons