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Peter has $12 in nickels and quarters. Altogether, he has 72 coins. Use the variables n and q to write and solve a system of equations to determine how many of each coin she has.

1 Answer

11 votes

Explanation:

n= nickels

q= quarters

Create a system of equations

n + q =72 number of coins

0.05n + 0.25q = 12 amount in money

solve by elimination ( anything would be fine)

n + q = 72

4( 0.05n + 0.25q = 12)

n+ q = 72

-

0.2n + q = 48

0.8n = 24

n= 30

now use substitution to find how many quarters she has

30 + q = 72

q = 42

He has 30 nickels and 42 quarters

Sorry for skipping some steps

I hope this helps!!!

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