the core principles of economics — end of chapter problem jia is considering whether to go out to dinner at a restaurant with her friend. the meal is expected to cost $40, jia typically leaves a 20% tip, and an uber will cost $5 each way. jia values the restaurant meal at $25. jia enjoys her friend’s company and is willing to pay $30 just to spend an evening with her. if jia does not go out to the restaurant, she will eat at home, using groceries that cost her $8.