Question

Ali went to the supermarket to buy 3 sweets and 8 bars of chocolate. He paid $29. If 8 sweets and 3 bars of chocolate cost $15, find the average cost of 2 sets and 2 bars of chocolate.
Steve
there is no average cost. The cost of the items does not change.

3s+8c = 29
8s+3c = 15

11s+11c = 44
Multiply by 2/11 and you have
2s+2c = 8