Question 361661
A piggy bank has only nickels and quarters in it. There are 12 coins worth $1.80. How many nickels and quarters are in the bank?
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Quantity Eq.: n + q = 12
Value Eq:::: 5n +25q= 180
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Multiply thru the Quantity Eq. by 5 to get:
5n + 5q = 60
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Subtract that from the value Equation and solve for "q":
20q = 120
q = 6 (# of quarters)
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Since n+q=12, n = 6 (# of nickels)
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Cheers,
Stan H.