A client plans to send a child to college for four years starting 18 years from
now. Having set aside money for tuition, she decides to plan for room and
board also. She estimates these costs at $20,000 per year, payable at the beginning
of each year, by the time her child goes to college. If she starts next year
and makes 17 payments into a savings account paying 5 percent annually, what
annual payments must she make?


答案没有用BGN模式算算4年的PV，不知道为什么，请赐教