SOLUTION: A money box contains only 20 cent coins and 50 cent coins. If there are 57 coins in the moneybox and their total value is $24.30, how many 20 cent coins and how many 50 cent coins

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Question 955458: A money box contains only 20 cent coins and 50 cent coins. If there are 57 coins in the moneybox and their total value is $24.30, how many 20 cent coins and how many 50 cent coins are there?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A money box contains only 20 cent coins and 50 cent coins. If there are 57 coins in the moneybox and their total value is $24.30, how many 20 cent coins and how many 50 cent coins are there?
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Equation:
Quantity:: t + f = 57 coins
Value:: 20t+50f = 2430 cents
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Simplify for elimination:
2t + 2f = 2*57
2t + 5f = 243
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Subtract and solve for "f":
3f = 129
f = 43 (# of 50 cent coins)
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t = 57-43 = 14 (# of 20 cent coins)
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Cheers,
Stan H.
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