Question

A store is having a sale on walnuts and chocolate chips. For 2 pounds of walnuts and 3 pounds of chocolate chips, the total cost is $11. For 4 pounds of walnuts

and 8 pounds of chocolate chips, the total cost is $25. Find the cost for each pound of walnuts and each pound of chocolate chips.

Answer 1

Walnuts cost $3.25 a point and chocolate chips cost $1.50 a pound

Explanation:

Let w = the cost of walnuts per pound

Let c = the cost of chocolate chips per pound.

2w + 3c = 11

4w + 8c = 25

Multiply the first equation by -2 and then add it to the second equation

-4w - 6c + = -22

4w + 8c = 25

2c = 3 Divide both sides by 2

c =
`(3)/(2)` = $1.50

The chocolate chips cost $1.50 per pound

Substitute 1.50 for c into either the of the 2 original equations

2w +3(1.50) = 11

2w + 4.50 = 11 Subtract 4.50 from both sides

2w = 6.50 Divide both sides by 2

w = 3.25

The walnuts cost 3.25 per pound

Check

2w + 3c = 11

2(3.25) +3(1.50) = 11

6.50 + 4.50 = 11

11 = 11

4w + 8c = 25

4(3.25) + 8(1.50) = 25

13 + 12 = 25

25 = 25