Question

Members of a senior class held a car wash to raise funds for their senior prom. They charged $3 to wash a car and $5 to wash a pick-up truck or a sport utility vehicle. If they earned a total of $275 by washing a total of 75 vehicles, how many cars did they wash?

Answer 1

Answer:the number of cars that were washed is 50

Explanation:

Let x represent the number of cars that members of a senior class.

Let y represent the number of pick-up truck or a sport utility vehicle that members of a senior class.

They charged $3 to wash a car and $5 to wash a pick-up truck or a sport utility vehicle and they earned a total of $275. This means that

3x + 5y = 275 - - - - - - - - -- - -1

They washed a total of 75 vehicles. This means that

x + y = 75

Substituting x = 75 - y into equation 1, it becomes

3(75 - y) + 5y = 275

225 - 3y + 5y = 275

- 3y + 5y = 275 - 225

2y = 50

y = 50/2 = 25

Substituting y = 25 into x = 75 - y, it becomes

x = 75 - 25 = 50