Question

A store is having a sale on walnuts and chocolate chips. For 2 pounds of walnuts and 5 pounds of chocolate chips, the total cost is $13. For 8 pounds of walnuts and 3 pounds of chocolate chips, the total cost is $18. Find the cost for each pound of walnuts and each pound of chocolate chips.

Answer 1

let x=cost/lb of walnuts

let y=cost/lb of chocolate chips

..

3x+5y=16

6x+2y=22

6x+10y=32 (mult. eq by 2)

6x+2y=22

subtract:

8y=10

y=10/8=1.25

x=16-5y=9.75

cost/lb of walnuts=$1.25

cost/lb of chocolate chips=$9.75