Question 570065
Joe's Coffee Shop makes a blend that is a mixture of two types of coffee. 
Type A coffee costs Joe $5.40 per pound, and type B coffee costs $4.20 per pound. This month's blend used twice as many pounds of type B coffee as type A, for a total cost of $372.60 . How many pounds of type A coffee were used?
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Equations:
Quantity Eq:::B = 2A
Value Eq:::::5.4A + 4.2B = 372.6
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Substitute for "B" and solve for "A":
5.4A + 4.2(2A) = 372.6
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5.4A + 8.4A = 372.6
13.8A = 372.6
A = 27 lbs (amt. of Type A coffee needed)
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Cheers,
Stan H.
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