Question

A coffee supply store waits until the orders for its special blend reach 100 pounds before making up a batch. Columbian coffee selling for $8.85 a pound is blended with Brazilian coffee selling for $3.85 a pound to make a product that sells for $6.55 a pound. How much of each type of coffee should be used to make the blend that will fill the orders?

Answer 1

x - Columbian coffee ( in pounds),
y - Brazilian coffee ( in pounds );
x + y = 100
8.85 x + 3.85 y = 6.55 ( x + y )
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x = 100 - y
8.85 ( 100 - y ) + 3.85 y = 6.55 * 100
855 - 8.55 y + 3.85 y = 655
- 5 y = - 230
y = ( - 230 ) : ( - 5 )
y = 46
x = 100 - 46
x = 54
Answer: 54 pounds of Columbian coffee and 46 pounds of Brazilian coffee should be used.