SOLUTION: A purse has $1.15 in nickels and dimes and has 20 coins. How many dimes are in the purse.

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Question 745806: A purse has $1.15 in nickels and dimes and has 20 coins. How many dimes are in the purse.
Answer by FrankM(1040) About Me  (Show Source):
You can put this solution on YOUR website!
x is number of nickels
y is number of dimes
5x + 10y = 115
x + y = 20 as there are 20 coins total.
10x + 10y = 200 (multiplie last equation, both sides by 10)
5x + 10y = 115 (first equation)
5x = 85 (subtracted second equation from first here )
x = 17 (85 cents)
y = 3 (30 cents)