<PRE><B>Question 118088</B>
A stamp collection consists of 5, 13, and 18 cent stamps. 
The number of 13 cent stamps is one less than twice the number of 5 cent stamps.
Let # of 5 cent stamps be &quot;x: Value is 5x cents
# of 13 cent stamps is 2x-1; value is 13(2x-1)=26x-13 cents
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The number of 18 cent stamps is five more than the number of 13 cent stamps.
# of 18 cent stams is 2x-1+5 = 2x+4; value is 18(2x+4)= 36x+72 cents
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 The total value of all the stamps is $2.60.
EQUATION:
value + value + value = 260 cents
5x+26x-13+36x+72 = 260
67x +59 = 260
67x = 201
x = 3 
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Find the number of 13 cent stamps in the collection.
26x-13 = 26*3-13 = 65 (# of 13-cent stamps)
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Cheers,
Stan H.
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