Kenny is very concerned he is 52 years old and has not been able to save any towards his retirement. His friends and family have been telling him for years that he must save for retirement and that he wont be able to work forever. But he has disregarded them by saying he chooses not to worry about that now. But after having a long conversation with his friend Lenny he decided that he would really like to retire when he is 65 years old and travel. He figures out he would need two payments of $2,500 a year, but he can only invest $17,500 today. Lenny is a little concerned for Kenny and if he is going to be able to initiate his plan.

Because Lenny knows investments and Kenny would need an interest rate of how much to be able to retire at 65 years old?