Question 1008664: A person has 21 coins. They're made up of quarters and dimes. In total he has $3.45. How many quarters and dimes were there Answer by fractalier(6550) (Show Source):
You can put this solution on YOUR website! Call the number of quarters and dimes, q and d.
Thus we have
q + d = 21
and for our value equation we have
25q + 10d = 345 (we work in cents)
Now multiply the top by 25 and subtract...we get
25q + 10d = 345
-(25q + 25d = 525)
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-15d = -180
d = 12 dimes
q = 9 quarters
