Answers
Number of nickels = 16
Number of quarters = 8
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Work Shown
The nickels, dimes and quarters are in the ratio 2:2:1 which means we have 2x nickels, 2x dimes and 1x quarters for some positive whole number x.
We have 16 dimes. Set 2x equal to 16 and solve for x.
2x = 16
x = 16/2
x = 8