SOLUTION: Marcus has a change jar that contains only nickels and quarters. He has 69 coins which add up to a total of $12.45. How many of each type of coin does he have?

Question 1008989: Marcus has a change jar that contains only nickels and quarters. He has 69 coins which add up to a total of $12.45. How many of each type of coin does he have?

Found 2 solutions by ikleyn, fractalier:
Answer by ikleyn(52810) (Show Source): You can put this solution on YOUR website!
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Marcus has a change jar that contains only nickels and quarters. He has 69 coins which add up to a total of $12.45.
How many of each type of coin does he have?
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Assume for a minute that all 69 coins are nickels, and analyse the situation further. It will help you to solve the problem.

If you still need help, see the lesson Solving coin problems without using equations in this site.

Answer. = 45 quarters and 69-45 = 24 nickels.

Answer by fractalier(6550) (Show Source): You can put this solution on YOUR website!
Call the number of nickels and quarters, n and q.
Thus we have
n + q = 69
The value equation is
5n + 25q = 1245 (we work in cents)
Now multiply the top equation by five and subtract and we get
5n + 25q = 1245
-(5n + 5q = 345)
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20q = 900
q = 45 quarters so that we have
n = 69-45 = 24 nickels
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