Question 563813
68 coins, all of which are 20 c or 50c pieces, amount to $25.30. find how many there are of each coin.
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Quantity Eq::: t  +  f  = 68 coins
Value Eq:::: 20t + 50f  = 2530 cents
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Multiply 1st thru by 20:
20t  +  20f  = 20*68
20t  +  50f  = 2530
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Subtract and solve for "f":
30f = 1170
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f = 39 (# of 50c coins)
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t = 68-39 = 29 (# of 20c coins)
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Cheers,
Stan H.
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