Question 1039022
A collection of nickels, dimes, and quarters consist of 

60 coins with a total of 

$6.00. If there are 

2 times as many dimes as quarters, find the number of each type of coins.
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n + d + q = 60
d = 2q
5n + 10d + 25q = 600
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n + 3q = 60
5n + 45q = 600 --> n + 9q = 120
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n + 9q = 120
n + 3q = 60
------------------ Subtract
6q = 60
q = 10 quarters
d = 20 dimes
n = 30 nickels