Question 1042173: Molly has 14 coins, all of which are quarters and nickels. In all, they're worth $2.50. How many of each kind of coin does Molly have? Answer by fractalier(6550) (Show Source):
You can put this solution on YOUR website! Let us call the numbers of quarters and nickels, q and n.
Then we can write
q + n = 14
and the value equation is
25q + 5n = 250 (we work in cents)
Now we will multiply the top equation by five and subtract it from the bottom equation...like this...
25q + 5n = 250
-(5q + 5n = 70)
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20q = 180
q = 9 quarters
which means
n = 5 nickels