Question 920612
1. The amount of money in a bag is $7.70. There are 62 coins consisting of nickels, dimes, and quarters. If there are three times as many dimes as nickels, how many coins of each are there?
Value Equation:: 5n + 10d + 25q = 770 cents
Quantity Eq::::: n + d + q = 62
Quandity Eq::::: d = 3n
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Modify::
n + 2d + 5q = 154
n + d + q = 62
d = 3n
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Substitute::
n + 6n + 5q = 154
n + 3n + q = 62
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Simplified Form::
7n + 5q = 154
4n + q = 62
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Modify for elimination::
7n + 5q = 154
20n + 5q = 310
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Subtract and solve for "n":
13n = 156
n = 12 (# of nickels)
d = 3n = 36 (# of dimes)
n + d + q = 62 
12 + 36 + q = 62
q = 14 (3 of quarters)
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Cheers,
Stan H.
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