NO.PZ2022123001000005
问题如下:
A couple plans to pay their child’s college tuition for 4 years starting 18 years from now. The current annual cost of college is C$7,000, and they expect this cost to rise at an annual rate of 5 percent. In their planning, they assume that they can earn 6% annually. How much must they put aside each year, starting next year, if they plan to make 17 equal payments?
选项:
A.$2,221.58
B.$2,300.78
C.$3,038.74
解释:
Step1: calculate the CF since 18,
CF18=7000*(1+5%)18 =16846, CF19=7000*(1+5%)19 =17689,…
Step 2: PV of tuition (4 CF since 18) at year 17
C$16,846 (1,06)-1 + C$17,689 (1.06)-2 + C$18,573 (1.06)-3 + C$19,502 (1.06 )-4 =$62,677
Step 3: Calculate PMT
Input FV=C$62,677, PV=0, I/Y=6, N=17, then CPT PMT= C$2,221.58
In summary, the couple will need to put aside C$2,221.58 each year if they start next year and make 17 equal payments.
题干里说明年开始支付一直到第18年,一共支付17年。
支付完最后一笔PMT应该刚好到了第18年。
所以学费应该从第18年开始而不是第17年,为什么答案里4年学费还要折现到第17年而不是折现到第18年?