An individual is faced with the following two problems. Please advice him as a consultant what should he do?

1. Mr Zekis local pizza store wants to include him to a promotional program on a monthly basis. Each month two large pizzas are free of charge and 5$ per pizza after the first two. Otherwise (if he does not join) he pays $4 per pizza. Under which conditions should he join the promotion program? At which point would he be indifferent whether to join or not?

Mr. Zeki is about to retire and wants to make an investment for his retirement years. He wants to purchase a car worth of 250.000TL and he knows that the market value depreciates at the real rate (i.e., after inflation adjustment) of 5% per year. He plans to sell the car after 6 years and upgrade it to a new model which he thinks that he can purchase for 320.000TL at that time (i.e, 6 years from now). Mr. Zeki, being an intelligent person does not want to put an additional financial burden on himself during the retirement years and he wants to spare some money today that would allow him to have a brand new car six years from now. How much should he deposit to a time deposit account (vadeli hesap) at a real interest rate of 8% so that he can purchase upgraded car and the sale price of the old car?