Billy and Julia go to the Sportarama store to buy baseball jerseys. The store is having a sale. If you buy one jersey at the regular price, the second jersey is half price. You must pay full price for the more expensive jersey. Billy wants to buy a jersey for thirty dollars and fifty cents. Julia wants to buy a jersey for fifty dollars. Julia suggests that they buy the two jerseys together and each of them pay half of the total cost. Billy says that Julia will save more money than he will if they follow her suggestion. Is Billy correct? Show all your mathematical thinking.