Find the cost per pound of a coffee mixture made from 4 lb of coffee that costs $9.10 per pound and 16 lb of coffee that costs $5.30 per pound.

Question

Find the cost per pound of a coffee mixture made from 4 lb of coffee that costs $9.10 per pound and 16 lb of coffee that costs $5.30 per pound.

Answer 1

4(9.1) + 16(5.30) = 20x

20x = 36.4 + 84.8 = 121.2

x = 121.2/20 = $6.06 per pound, 20 pounds

or look at it another way

9.10 - 6.06 = 3.04

6.06 - 5.30 = 0.76

3.04/.76 = 4

16/4 = 4

you need 4 times as much of the 5.30 as of 9.10. 16 is 4 times as much