Question

A family has two cars. During one particular week, the first car consumed 15 gallons of gas. The two cars Drove a combined total of 1475 miles and the sum of their fuel efficiency was 65 miles per gallon. What were the fuel efficiency of each of the cars that week?

Answer 1

Car 1 : 40 miles per gallon

Car 2: 25 miles per gallon

Explanation:

family has two cars. During one particular week, the first car consumed 15 gallons of gas. The second car consumed 25 gallons of gas. The two cars Drove a combined total of 1475 miles and the sum of their fuel efficiency was 65 miles per gallon. What were the fuel efficiency of each of the cars that week

Given that :

Fuel efficiency , car 1 = x

Fuel efficiency , car 2 = y

x + y = 65 - - (1)

15x + 35y = 1475 - - - (2)

x = 65 - y

15(65-y) + 35y

975 - 15y + 35y = 1475

20y = 14875 - 975

20y = 500

y = 25

Put y = 25 in (1)

x + y = 65

x + 25 = 65

x = 65 - 25

x = 40