If you invest P dollars at the beginning of every week. However, a banker decides to compound interest at rate r at the end of weeks 5, 9, 12, 14, 15. What is the value of the account at the end of week 15? 1

At the end of week 15, you need to spend 15000. how much money should you invest weekly to ensure you have exactly 15000 after week 15 if the weekly interest rate is 10%? 2