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Jimmy has a pocket full of nickels and quarters. Their are a total of 40 coins. When he added it all up he had $5.20. How many nickels did he have?

1 Answer

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Assuming x = nickels, y = quarters


x + y = 40 \\ 0.05x + 0.25y = 5.20


x + y = 40 \\ x = 40 - y

Substitute that into

0.05(40 - y) + 0.25y = 5.20 \\ 2 - 0.05y + 0.25y = 5.20 \\ 0.2y = 3.20 \\ y = 16

Substitute that into

x + 16 = 40 \\ x = 24

Answer : He has 24 nickels.

Hope this helps. - M
User Yohan Blake
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