Question 241479: Is it possible to spend $30 for 100 stamps consisting of 20-cent stamps and 33-cent stamps? Found 2 solutions by checkley77, stanbon:Answer by checkley77(12844) (Show Source):
You can put this solution on YOUR website! x+y=100 or x=100-y
.20x+.33y=30
.20(100-y)+.33y=30
20-.20y+.33y=30
.13y=30-20
.13y=10
y=10/.13
y=76.9 33 cent stamps.
Ans. is NO.
You can put this solution on YOUR website! Is it possible to spend $30 for 100 stamps consisting of 20-cent stamps and 33-cent stamps?
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Equations:
Quantity: t + r = 100
Value::: 20t+33r = 3000
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Multiply thru the Quatity Eq. by 20 to get:
20t + 20r = 2000
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Subtract that from the Value Eq. to get:
13r = 1000
r = 76.92
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Since r is the number of thirty cent stamps and is not
an integer the combination does not work.
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Cheers,
Stan H.