How many pounds of brand X coffee which costs $12/lb must be added to 4lbs of brand Y coffee which costs $6/lb to make a special blend which costs $8/lb?

Question

I have to solve this with 2 equations. How should I do that?

Answer 1

$12X + $6(4) = (X+4)*$8

 

12X + 24 = 8(x+4)

 

12x + 24 = 8x + 32

 

12x + 24 - 8x - 32 = 0

 

4x - 8 = 0

 

4x = 8

 

x = 8/4 = 2

 

12(2) + 4(6) = 24 + 24 = 48 = 6*8