The first step calculates the amount of Father's annual retirement amounts, the amount he will withdraw each year once he turns 60 . This will have the same purchasing power as $60K today. That needs a future value calculation. Step 2 calculates how much his initial $100,000 investment will grow to in 10 years. Step 3 calculates the PV of his 25 retirement withdrawals. It's an annuity due because he takes his first withdrawal at the same time as his last contribution. Step 4 is step 3 step 2 Step 5 is the PMT needed to get to the Step 4 value in 10 hears. f f