Question 831954
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