how much for each pound

Question

A store is having a sale on jelly beans and almonds. For 2 pounds of jelly beans and 3 pounds of almonds, the total cost is $9. For 4 pounds of jelly beans and 8 pounds of almonds, the total cost is $21. Find the cost for each pound of jelly beans and each pound of almonds.

cost for each pound of jelly beans?

cost for each pound of almonds

Answer 1

2j + 3a = 9

4j + 8a = 21

Multiply the first equation by -2:

-4j -6a = -18

4j + 8a = 21

Add the equations and solve for a and j.