This is a classic retirement problem. You are 25 years old and hope to retire at 70 years old. You expect to live another 25 years while you're retired. During those 25 years that you're living in retirement, you'd like to be able to withdraw $13,500 EVERY month at the beginning of the month. You can earn an average of 7.2% in your ETF during the years that you're still working. But during retirement, you expect to be able to earn only 6%.

1. How much must you have saved PRIOR to retirement, so that you can make your withdrawals DURING retirement?

2. How much must you save monthly DURING your working years to have accumulated the sum from #1 above?

3. You just won the lottery. Rather than making monthly payments into your retirement account, you've decided to make a single lump-sum payment into your retirement fund on your 25th birthday. What amount must you deposit at age 25 to have it compound monthly to have enough to fund the withdrawals during retirement? This sum continues to compound monthly and the interest rate earned prior to retirement is 7.2%.

JUST ANSWER NUMBER 3