SOLUTION: "Penelope spent all but a nickel of her $10 allowance on chocolate and bubblegum. She bought a total of 4.5 pounds of candy with chocolate costing 3.50/pound and bubblegum costing 
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Question 831954:  "Penelope spent all but a nickel of her $10 allowance on chocolate and bubblegum. She bought a total of 4.5 pounds of candy with chocolate costing 3.50/pound and bubblegum costing .60/pound. How much chocolate and bubblegum did she buy?"
Thank you! x 
Answer by josgarithmetic(39630)   (Show Source): You can put this solution on YOUR website!
 She spent $9.95 on the mixture of candy.
c for pounds of chocolate
b for pounds of bubblegum
c+b=4.5  accounting for pounds of the candy
3.5c+0.6b=9.95  accounting for cost
Modify the cost equation to have all whole numbers.
35c+6b=99.5 ---------- NOT QUITE ALL WHOLE NUMBERS but still useful.  This was multiplying left and right by 10.
If you multiply the poundage equation by 6, it becomes 6c+6b=27.
Now look at the way the system is:
6c+6b=27 and 35c+6b=99.5
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Subtract the "27" equation from the "99.5" equation and this eliminates the 6b.  You will easily get a value for c.  This is the Elimination Method.
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35c+6b-(6c+6b)=99.5-27
29c=72.5
c=2.5 pounds for the chocolate candy
This means b=2.0 pounds of bubblegum 
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