SOLUTION: 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. The number of 18 cent stamps is five more
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-> SOLUTION: 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. The number of 18 cent stamps is five more
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Question 116284: 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. The number of 18 cent stamps is five more than the number of 13 cent stamps. The total value of all the stamps is $2.60. Find the number of 13 cent stamps in the collection.
So far, I have a= 5 cent stamps, b= 13 cent stamps and c = 18 cent stamps.
b= 2a-1
c= (2a-1)+5
You can put this solution on YOUR website! Those two equations for b anc c are correct.
The last one is the value equation that gives the value of the entire collection.
You use the value of each stamp multiplied by the number of each stamp to give the total value.
If you substitute your two equations from above into this equation,
you will solve for a.
Then you can back substitute to find b and c.
Try it and if you get stuck, post another question.
