SOLUTION: Richard has a piggy bank containing only dimes and quarters. He has seven more quarters than dimes. If the total value of the coins is $3.85, how many dimes and quarters does Richa

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: Richard has a piggy bank containing only dimes and quarters. He has seven more quarters than dimes. If the total value of the coins is $3.85, how many dimes and quarters does Richa      Log On


   

Question 490789: Richard has a piggy bank containing only dimes and quarters. He has seven more quarters than dimes. If the total value of the coins is $3.85, how many dimes and quarters does Richard have?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
He has seven more quarters than dimes. If the total value of the coins is $3.85, how many dimes and quarters does Richard have?
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Equations:
q = d + 7
10d + 25q = 385 cents
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Substitute for "q" and solve for "d":
10d + 25(d+7) = 385
10d + 25d + 175 = 385
35d = 210
d = 6 (# of dimes)
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Solve for "q":
q = d+7
q = 6+7 = 13 (# of quarters)
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Cheers,
Stan H.