Question 349191
Hello, 
Let's have x be the cost for coffee and y be the cost for butter. We can set up 2 equations from this:
7x+10y=58.5
7x+5y=39.75
Multiply the second equation by -2 to get:
-14x-10y= -79.5
Now add this to the first equation to get:
-7x=-21
Now divide both sides by -7 to get:
x=3
y=3.75
There we go--butter is $3.75 per pound.
Make sense?
RJ
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