Question 143289: Sorry, but i need help with this one also. Thank you in advance.
Joe has a collection of nickels and dimes that is worth $5.65. If the number of dimes were doubled and the number of nickels were increased by 8, the value of the coins would be $10.45. How many dimes does he have?
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! Joe has a collection of nickels and dimes that is worth $5.65.
5n + 10d = 565 cents
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If the number of dimes were doubled and the number of nickels were increased by 8, the value of the coins would be $10.45.
5(n+8) + 10(2d) = 1045 cents
5n+40 + 20d = 1045
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How many dimes does he have?
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EQUATIONS:
5n + 10d = 565
5n + 20d = 1005
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10d = 440
d = 44 (# of dimes)
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Substitute into 5n+10d = 565 to solve for "n":
5n +440 = 565
5n = 125
n = 25 (# of nickels)
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Cheers,
Stan H.
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