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You have 31 coins consisting of nickels and

dimes. The coins total $2.25. How many coins
are nickels? How many are dimes?

1 Answer

4 votes

Answer:

There are 14 dimes and 17 nickels.

Explanation:

Let x be number of nickels and let y be number of dimes.

Given that the total is $2.25 and there are 31 coins, we know that:


0.05x +0.10y = 2.25


x+y = 31

Solving for x yields:


x=31-y

We then proceed by plugging that back into the previous equation:


0.05(31-y)+0.10y=2.25


1.55 - 0.05y +0.10y = 2.25\\ --> Distribute


1.55 +0.05y=2.25 --> add y's together


0.05y=0.7 --> subtract 1.55


y=14 --> divide by 0.05

Therefore, x must equal 17, which means you have 14 dimes and 17 nickels.

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