SOLUTION: Rita has a collection of 105 coins consisting of nickels, dimes, and quarters. The number of dimes is 5 more than one-third the number of nickels, and the number of quarters is twi

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Question 461117: Rita has a collection of 105 coins consisting of nickels, dimes, and quarters. The number of dimes is 5 more than one-third the number of nickels, and the number of quarters is twice the number of dimes. How many coins of each kind does she have?
Answer by stanbon(75887) About Me  (Show Source):
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Rita has a collection of 105 coins consisting of nickels, dimes, and quarters. The number of dimes is 5 more than one-third the number of nickels, and the number of quarters is twice the number of dimes. How many coins of each kind does she have?
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Quantity Equation: n + d + q = 105 coins
Quantity Equation: d = (1/3)n + 5
Quantity Equation: q = 2d
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Substitute for d and q and solve for "n":
n + (1/3)n + 5 + 2d = 105
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(4/3)n + 5 + (2/3)n + 10 = 105
2n + 15 = 105
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2n = 90
n = 45 (number of nickels)
d = (1/3)n+5 = 15+5 = 20 (number of dimes)
q = 2d = 40 (number of quarters)
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Cheers,
Stan H.