A food store makes a 11-pound mixture of peanuts, almonds, and raisins. The cost of peanuts is $1.50 per pound, almonds cost $3.00 per pound, and raisins cost $1.50 per pound. The mixture calls for twice as many peanuts as almonds. The total cost of the mixture is $21.00. How much of each ingredient did the store use?

A. 3lbs peanuts, 6 lbs almonds, 2 lbs raisins

B. 8 lbs peanuts, 1 lb almonds, 2 lbs raisins

C. 6 lbs peanuts, 3 lbs almonds, 2 lbs raisins

D. 8 lbs peanuts, 2 lbs almonds, 1 lbs raisins

Given: 11-pound mixture of peanuts, almonds, and raisins

Cost:

peanuts - 1.5 per pound

almonds - 3 per pound

raisins - 1.5 per pound

mixture:

twice as many peanuts as almond; total cost of mixture is 21.

a + p + r = 11 lbs

a + 2a + r = 11 lbs

3a + r = 11

r = 11 - 3a

1.5 (2a) + 3a + 1.5r = 21

3a + 3a + 1.5r = 21

6a + 1.5r = 21

6a + 1.5 (11-3a) = 21

6a + 16.5 - 4.5a = 21

6a - 4.5a = 21 - 16.5

1.5a = 4.5

1.5a/1.5 = 4.5/1.5

a = 3

almonds = 3 lbs

peanuts = 2a = 2 (3) = 6lbs

raisins = 11 - 3a = 11 - 3 (3) = 11 - 9 = 2 lbs

My answer is: C. 6 lbs peanuts, 3 lbs almonds, 2 lbs raisins