6 lol + 3 ice = 8.52
3 ice + 6 drink = 9.24 add them
6 lol + 3 ice + 3ice + 6 drink = 8.25 + 9.24 then divide by 6
You did not ask for the price of each! In fact, since you have only two equations with three unknown prices, you can't solve for individual prices. However, it happens that the two given equations reduce to a single equation that gives the "average cost" as well as the total cost of one of each of the three items which was what you asked.