Donna's Coffee Shop makes a blend that is a mixture of two types of coffee.

Question

Donna's Coffee Shop makes a blend that is a mixture of two types of coffee. Type A coffee costs Donna
$4.40
per pound, and type B coffee costs
$5.60
per pound. This month, Donna made
141
pounds of the blend, for a total cost of
$686.40
. How many pounds of type B coffee did she use?

Answer 1

A = type A coffee

B = type B coffee

 

A + B = 141  (this is the weights)

4.4A + 5.6B = 686.4  (this is the costs)

 

B = 141 - A  (substitute in the second eqution)

 

4.4A + 5.6 (141 - A) = 686.4

4.4A + 789.6 - 5.6A  = 686.4

-1.2A = -10.32

A = 86

 

Donna used 86 pounds of type A and 55 pounds of type B.