You can make two equations and solve as simultaneous equations:

Peanuts sell for $4.50 per pound and cashews sell for $14.00 per pound: [ 4.5p and 14c]

...a mixture that will sell for $6.88 per pound: [4.5p + 14c (6.88 x 28)]

How many pounds of peanuts and cashews must be used to create 28 pounds: [p + c = 28]

4.5p + 14c = (6.88 x 28) = 192.64

p + c = 28

Multiply the bottom equation by 4.5 and subtract it from the top equation:

4.5p + 14c = 192.64

4.5p + 4.5c = 126

This leaves:

9.5c = 66.64

c = 7.01

substitute c = 7 in [p + c = 28]

p + 7 = 28

p = 21

The mixture must contain 21 pounds of peanuts.

The mixture must contain 7 pounds of cashews.

Let P lb be the weight of peanuts needed; C lb of Cashews needed, then

4.5P+14C=6.88(28)=192.64-----(1)

P+C=28----------(2)

Solving the system of (1) & (2) for P & C, get

P=20.98127~21

C=7.014736~7

Thus,

21 lb of peanuts & 7 lb of Cashews

are needed.

THANK YOU!!!!!!!

Let W= 28 lbs. You can think of the price of W as W*P where P = price/pound

W*P = 4.50*p + 14*(W - p) since the amount of cashews is just the the amount of mix minus the amount of peanuts

28*6.88 = -9.50p + 14 *28 --> p = 28*(14-6.88)/9.5 = 21 lbs

Hence Weight of cashew = 28 - 21 = 7 lbs