SOLUTION: Ryan's Coffee Shop makes a blend that is a mixture of two types of coffee. Type A coffee costs Ryan $5.95per pound, and type B coffee costs $4.65 per pound. This month's blend used

Algebra ->  Expressions-with-variables -> SOLUTION: Ryan's Coffee Shop makes a blend that is a mixture of two types of coffee. Type A coffee costs Ryan $5.95per pound, and type B coffee costs $4.65 per pound. This month's blend used      Log On


   



Question 747390: Ryan's Coffee Shop makes a blend that is a mixture of two types of coffee. Type A coffee costs Ryan $5.95per pound, and type B coffee costs $4.65 per pound. This month's blend used twice as many pounds of type B coffee as type A, for a total cost of$320.25 . How many pounds of type A coffee were used?

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +a+ = pounds of type A coffee used
Let +b+ = pounds of type B coffee used
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given:
(1) +b+=+2a+
(2) +5.95a+%2B+4.65b+=+320.25+
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(2) +595a+%2B+465b+=+32025+
Substitute (1) into (2)
(2) +595a+%2B+465%2A2a+=+32025+
(2) +595a+%2B+930a+=+32025+
(2) +1525a+=+32025+
(2) +a+=+21+
and
(1) +b+=+2a+
(1) +b+=+42+
21 pounds of type A coffee were used
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check:
(2) +5.95a+%2B+4.65b+=+320.25+
(2) +5.95%2A21+%2B+4.65%2A42+=+320.25+
(2) +124.95+%2B+195.3+=+320.25+
(2) +320.25+=+320.25+
OK