Four college students decide to throw a party to celebrate the start of the school year but they are all broke so they decide to share the expenses equally. Aaron buys a “take-and-bake” pizza for $8, Randy buys $5 worth of ice cream; Seth spends $2 on a bag of ice, and Dave gets $3 worth of soft drinks. In addition, he pays $6 on some cupcakes. To be fair, who owes money to whom?