a merchant wants to stock the shelves with 100 Ibs. of a mixed nuts that cost $8.00 a Ibs. the merchant has cashews and peanuts. peanuts cost $6.00 a Ibs. and cashews cost $12.00 a Ibs. how many Ibs. of each should the merchant use in the mixture?

C=weight of cashews in lbs

100-C = weight of peanuts (lbs)

12C + 6(100-C) = 100*8
6C = 800-600
C=200/6=33.33lbs (approx.)
Peanuts = 100-33.33=66.67 lbs (approx.)