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=#number of cars

#t=#number of trucks

There are 32 vehicles in total, so:

#c+t=32#

#t=32-c#

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

#5c+8t=199#

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

#5c+256-8c=199#

#256-199=8c-5c#

#3c=57#

#c=19#

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

#32-19=13# trucks

Let's check our answer:

#19+13=32# vehicles

#19*5+13*8=95+104=$199#

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

Nov 20, 2017

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

Explanation:

Given -

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

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

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

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

Solve the 1st equation for #y#

#y=32-x#

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

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

#5x+256-8x=199#

#5x-8x=199-256=-57#
#-3x=-57#

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

Substitute #x=19# in equation (1)

#19+y=32#
#y=32-19=3#

#y=3#

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