Problem 1 Future Value

How many years until you want to retire? If you are saving monthly, multiply years by 12 to get the number of compounding periods. (30 years to my retirement)

How much do you want to invest per month? (PMT)

How much risk are you willing to bear? (I/Y)

What is the future value? CPT FV

Problem 2 Required Payment

Assuming N and I/Y are the same as problem 1,

How much do you want to have accumulated when you retire? (FV)

What is the required payment to reach your goal? CPT PMT