You can put this solution on YOUR website! A collection of 25 nickels and dimes is word $1.60. How many dimes are there?
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The hard way:
n = # of nickels, d = dimes
n + d = 25
5n+10d = 160 --> n+2d = 32
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n + 2d = 32
n + d = 25
----------- Subtract
d = 7 dimes
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Easier way:
25 nickels = $1.25
Each nickel replaced by a dime add 5 to the value
160 - 125 = 35 to be added
35/5 = 7
7 dimes
