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A parking meter contains nickels and quarters woth $5.90. There are 62 coins in all. Find how many of each there are
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Let n = # of nickels.
Then the number of quarters is (62-n).
Nickels contribute 5n cents to the total.
Quarters contribute 25*(62-n).
The total is 590 cents, and the "value equation" is
5n + 25*(62-n) = 590.
Simplify and solve for n:
5n + 25*62 - 25n = 590,
5n + 1550 - 25n = 590,
-20n = 590 - 1550,
-20n = 960,
n = 
= 48.
Answer. There are 48 nickels and 62-48 = 14 quarters.
Check. 48*5 + 14*25 = 590.
