SOLUTION: The Coffee Hut charges $9 per pound for Audioslave French Roast coffee and $8 per pound for Humble Pie Bold coffee. How much of each type should be used to make a 20-lb blend that

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: The Coffee Hut charges $9 per pound for Audioslave French Roast coffee and $8 per pound for Humble Pie Bold coffee. How much of each type should be used to make a 20-lb blend that      Log On


   



Question 1074468: The Coffee Hut charges $9 per pound for Audioslave French Roast coffee and $8 per pound for Humble Pie Bold coffee. How much of each type should be used to make a 20-lb blend that sells for $8.40 per pound?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +a+ = pounds of AFR coffee needed
Let +b+ = pounds of HPB coffee needed
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(1) +a+%2B+b+=+20+
(2) +%28+9a+%2B+8b+%29+%2F+20+=+8.4+
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(2) +9a+%2B+8b+=+168+
Multiply both sides of (1) by +8+
and subtract (1) from (2)
(2) +9a+%2B+8b+=+168+
(1) +-8a+-+8b+=+-160+
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+a+=+8+
and
(1) +8+%2B+b+=+20+
(1) +b+=+12+
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8 pounds of AFR coffee are needed
12 pounds of HPB coffee are needed
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check:
(2) +%28+9a+%2B+8b+%29+%2F+20+=+8.4+
(2) +%28+9%2A8+%2B+8%2A12+%29+%2F+20+=+8.4+
(2) +%28+72+%2B+96+%29+%2F+20+=+8.4+
(2) +168+=+8.4%2A20+
(2) +168+=+168+
OK