how many pounds of nuts selling for $9 per lb and raisins selling for $3 per lb should a person combine to obtain 60 lb of a trail mix selling for $5 per lb
Let n be the number of lbs of nuts. Let r be the number of lbs of raisins. 9n + 3r = 60 * 5 = 300 .............(1) n + r = 60 n = 60 - r ...............(2) Plugging the expression for n in (2) into (1) we get: 9(60 - r) + 3r = 300 which expands to: 540 - 9r + 3r = 300 .............(3) Simplifying and rearranging (3) we get: -6r = -240 Therefore r, the weight of raisins = 40 lbs and the weight of nuts is 60 - 40 = 20 lbs
