Question

Evan washes two types of vehicles. It takes him 30 minutes to wash a car and 40 minutes to wash a truck. He charges $12 to wash a car and $15 to wash a truck. In 270 minutes, Evan made $105 washing cars and trucks. How many trucks did Evan wash?

Answer 1

The answer is 3 i think

Answer 2

Answer:

$3\ trucks$

Step-by-step explanation:

Let

x-----> the number of cars

y----> the number of trucks

we know that

$30x+40y=270$ -----> equation A

$12x+15y=105$ -----> equation B

Using a graphing tool

Remember that the solution of the system of equations is equal to the intersection point both graphs

In this problem the intersection point is $(5,3)$

see the attached figure

therefore

$x=5\ cars$

$y=3\ trucks$