SOLUTION: Tim Whitman has $4.50 in change in his desk drawer to use on the vending ma- chines downstairs. He has four more quarters than dimes. He has three times as many nickels as dimes. H
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Question 1033249: Tim Whitman has $4.50 in change in his desk drawer to use on the vending ma- chines downstairs. He has four more quarters than dimes. He has three times as many nickels as dimes. How many coins of each type does he have? Found 2 solutions by addingup, stanbon:Answer by addingup(3677) (Show Source):
You can put this solution on YOUR website! q = d+4
n = 3d
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.05n+.10d+.25q = 4.50 Substitute for q and n:
.05(3d)+.10d+.25(d+4)= 4.50
.15d+.10d+.25d+1 = 4.50
.50d = 3.50
d = 7
q = 7+4 = 11
n = 3(7) = 21
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Check:
d = 7(.10) = .70
q = 11(.25)= 2.75
n = 21(.05)= 1.05
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Total: . . . 4.50 Correct
John
You can put this solution on YOUR website! Tim Whitman has $4.50 in change in his desk drawer to use on the vending ma- chines downstairs. He has four more quarters than dimes. He has three times as many nickels as dimes. How many coins of each type does he have?
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Equations:
q = d + 4
n = 3d
5n + 10d + 25q = 450 cents
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Substitute to get one variable::
5(3d) + 10d + 25(d+4) = 450
15d + 10d + 25d + 100 = 450
50d = 350
d = 7 # of dimes
n = 3d = 21 # of nickels
q = d+4 = 11 (# of quarters)
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Cheers,
Stan H.
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