Question

A family has two cars. The first car has a fuel efficiency of 20 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 1700 miles, for a total gas consumption of 50 gallons. How many gallons were consumed by each of the two cars that week?

Answer 1

Answer: 15 gallons and 35 gallons were consumed by first and second car respectively.

Explanation:

Since we have given that

Number of gallons of total gas consumption = 50

Number of total miles = 1700

Efficiency of first car = 20 miles per gallon

Efficiency of second car = 40 miles per gallon

Let the number of gallons consumed by first car be 'x'.

Let the number of gallons consumed by second car be '50-x'.

According to question, we get that

`20x+40(50-x)=1700\\\\20x+2000-40x=1700\\\\-20x=1700-2000\\\\-20x=-300\\\\x=(300)/(20)=15`

So, 50-x = 50-15 = 35 gallons.

Hence, 15 gallons and 35 gallons were consumed by first and second car respectively.