Question

Lamar's Coffee Shop makes a blend that is a mixture of two types of coffee. Type A coffee costs Lamar $4.90 per pound, and type B coffee costs $5.95 per

pound. This month's blend used four times as many pounds of type B coffee as type A, for a total cost of $602.70. How many pounds of type A coffee were
used?

Answer 1

Answer: 26 pounds

Explanation:

Let +a+ = pounds of coffee A used

Let +b+ = pounds of coffee B used

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(1) +4.1a+%2B+5.8b+=+709.8+

(2) +b+=+4a+

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(1) +41a+%2B+58b+=+7098+

Substitute (2) into (1)

(1) +41a+%2B+58%2A4a+=+7098+

(1) +41a+%2B+232a+=+7098+

(1) +273a+=+7098+

(1) +a+=+26+

26 pounds of coffee A were used

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check:

(2) +b+=+4a+

(2) +b+=+4%2A26+

(2) +b+=+104+

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(1) +41a+%2B+58b+=+7098+

(1) +41%2A26+%2B+58%2A104+=+7098+

(1) +1066+%2B+6032+=+7098+

(1) +7098+=+7098+