56.2k views
4 votes
Billy went to the Show and spent $78 on a combined total of 9 items including rides and showbags. If each showbag cost $12 and each ride cost $7, how many of each did Billy buy?

1 Answer

7 votes
First, set x for showbags and y for rides.
So now we need to make a system equations.
Since he bought 9 items, x+y=9.
And because he spent $78 and we know the price of each item, the second equation is 12x+7y=78.

Now solve for the system of equations by elimination.
12x+7y=78
-7(x+y=9)

Now the new equations are:
12x+7y=78
-7x-7y=-63

Now just subtract.
5x=15

x=3.

And since originally we made x represent showbags, he bought 3 showbags. Which means he bought 6 rides because 9-3=6.

If you wanna check your answer, just plug in.

x+y=9
3+6=9

12(3)+6(7)=78
36+42=78

Answer: Billy bought 3 showbags and 6 rides.


User InnisBrendan
by
7.4k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories