Answer:
I will need 26.4 pounds of the expensive nuts and 1.6 pounds of the cheap nuts.
Explanation:
Since I have one type of nut that sells for $ 4.50 / lb and another type of nut that sells for $ 8.00 / lb, and I would like to have 28 lbs of a nut mixture that sells for $ 7.80 / lb, to determine how much of each nut will I need to obtain the desired mixture, the following calculation must be performed:
8 x 0.95 + 4.5 x 0.05 = 7.825
8 x 0.94 + 4.5 x 0.06 = 7.79
0.94 x 28 = 26.32
26.4 x 8 + 1.6 x 4.5 = 218.4
218.4 / 28 = 7.8
Thus, I will need 26.4 pounds of the expensive nuts and 1.6 pounds of the cheap nuts.