You plan to retire in 30 years. At the end of that time, you wish to have $45,500, the approximate amount needed - see problem 5(b) - in order to withdraw $300.00 monthly for 20 years after retirement. (a) What amount must you deposit monthly at 5 percent? Hint. At the end of one month P=A; at the end of two months P=Ae^(0.05/12), where A is the monthly deposti.

(b) What amount must you deposit semiannually if interest is credited semiannually at 5 percent instead of continuously. Note. This problem no longer involves a differential equation.

The answers are:

(a) $45,000 = A[(1-e^1.5)/(1-e^(0.05/12))], A = $54.57 monthly

(b) $45,000 = A[((1.025)^60-1)/0.025], A = $334.58 semiannually

I just have no clue how to set up this problem.