Question 736645: john has twice the number of quarters as dimes. the amount of money in$1.80. find the number of dimes Found 5 solutions by stanbon, josmiceli, lynnlo, ikleyn, josgarithmetic:Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! john has twice the number of quarters as dimes. the amount of money in$1.80. find the number of dimes
Equations:
q = 2dan
10d + 25q = 180 cents
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Substitute for "q" and solve for "d":
10d + 25(2d) = 180
10d + 50d = 180
60d = 180
d = 3 (# of dimes)
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Solve for "q":
q = 2d
q = 2*3 = 6 (# of quarters)
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Cheers,
Stan H.
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You can put this solution on YOUR website! (1) ( in cents )
(2)
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(1)
(2)
Substitute (2) into (1)
(1)
(1)
(1)
(1)
and
(2)
(2)
(2)
There are 3 dimes
check:
(1)
(1)
(1)
OK
You can put this solution on YOUR website! TOTAL===============$1.80
DIMES===========3==.30
QUARTERS========6==$1.50
=========================
===================$1.80
You can put this solution on YOUR website! .
john has twice the number of quarters as dimes. the amount of money in$1.80. find the number of dimes
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This problem is easier to solve mentally than using equation/equations.
According to the problem, we can group coins in sets, placing two quarters and one dime in each set.
Then each set is worth 2*25 + 10 = 50 + 10 = 60 cents,
and there are 180/60 = 3 such sets.
Hence, the number of dimes John has is 3. ANSWER
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