<PRE><B>Question 714502</B>
A vending machine that takes only dimes and quarters contain 30 coins, with a total value of $4.20. How many of each coin are there?
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d + q = 30 (# of coins)
10d + 25q = 420 (total cents)
Can you do the rest?
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Another method:
30 dimes = $3.00
For each dime replaced by a quarter, 15 cents is added
420 - 300 = 120
120/15 = 8 quarters
22 dimes
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