Doug is the owner of the Burger Barn. Last year, the price of a hamburger was $2.50 and the price of a small fry was $1.25. This year, Doug has decided to raise the prices of these items but wants to keep them proportional to last year's prices. Determine an increased price of each item that is proportional to last year's prices. Then, simplify each rate to show that the increased prices are proportional to last year's prices.