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Question

Bill and Daniel are selling pies for a school fundraiser. Customers can buy cherry pies and blackberry pies. Bill sold 14 cherrys pies and 10 blackberry pies for a total of 150$. Daniel sold 10 cherry pies and 5 blackberry pies for a total of 90$. Find the cost each of one cherry pie and one blackberry pie.

Answer 1

Use C for cherry pie, and use B for blackberry pie

Bill sold 14C+10B=150

Daniel sold 10C+5B=90

Now multiply the second equation by -2 so we can cancel out the B

-2(10C+5B=90)

-20C-10B=-180

Now subtract:

14C+10B=150

-20C-10B=-180

The result is:

-6C=-30

C=5

Now plug C=5 back into one of the first equations so you can solve for B.

10C+5B=90 becomes

10(5) +5B=90

50+5B=90

5B=40

B=8

So cherry pies cost $5 a piece, and blackberry pies cost $8 a piece.