The drama club is having a car wash as a fundraiser. They wash cars for $5 each and trucks for $8 each. How many of each type of vehicle did they wash if they raised $199 by washing 32 vehicles?

2 Answers
Nov 20, 2017

19 cars, 13 trucks

Explanation:

Okay, let's start by defining our variables

c=c=number of cars

t=t=number of trucks

There are 32 vehicles in total, so:

c+t=32c+t=32

t=32-ct=32c

Now, let's use the other piece of information given in the problem (the amount of money):

5c+8t=1995c+8t=199

5c+8(32-c)=1995c+8(32c)=199

5c+256-8c=1995c+2568c=199

256-199=8c-5c256199=8c5c

3c=573c=57

c=19c=19

There are 19 cars. Therefore, the number of trucks is:

32-19=133219=13 trucks

Let's check our answer:

19+13=3219+13=32 vehicles

19*5+13*8=95+104=$199195+138=95+104=$199

It looks like our answers are correct and make sense. Hope this helps!

Nov 20, 2017

Number of cars x=19x=19
Number of trucks y=3y=3

Explanation:

Given -

Rate to wash one car =$.5=$.5
Rate to wash one truck =$.8=$.8
Total Amount collected =$.199=$.199
Number of vehicles =32=32

Let -
Number of cars be =x=x
Number of trucks =y=y

Based on the above pieces of information, we can form two equations

x+y=32x+y=32 --------------(1) Total cars and trucks washed
5x+8y=1995x+8y=199--------------(2) Total amount collected

Solve the 1st equation for yy

y=32-xy=32x

Substitute y=32-xy=32x in equation (2)

5x+8(32-x)=1995x+8(32x)=199

5x+256-8x=1995x+2568x=199

5x-8x=199-256=-575x8x=199256=57
-3x=-573x=57

x=(-57)/(-3)=19x=573=19

Substitute x=19x=19 in equation (1)

19+y=3219+y=32
y=32-19=3y=3219=3

y=3y=3

Number of cars x=19x=19
Number of trucks y=3y=3