Joshua needed money for some unexpected expenses, so he borrowed $5,355.26 from a friend and agreed to repay the loan in seven equal installments of $1,100 at the end of each year. The agreement is offering an implied interest rate of Joshuaâs friend, Willie, has hired a financial planner for advice on retirement. Considering Willieâs current expenses and expected future lifestyle changes, the financial planner has stated that once Willie crosses a threshold of $1,387,311 in savings, he will have enough money for retirement. Willie has nothing saved for his retirement yet, so he plans to start depositing $25,000 in a retirement fund at a fixed rate of 6.00% at the end of each year. It will takefor Willie to reach his retirement goal.