Level 1 Schweser Book 6 Page 52 interest, special, payments, deposits, investor

Dong86

In three years, an investor deposits the first of eight $1,000 payments into a
special fund. The fund will earn interest at the rate of 5% per year until the
end of the fifth year. Thereafter, all money accumulated in the fund will
earn a reduced interest rate of 4% compounded annually until the end of
the tenth year. How much money will the investor have in the fund at the
end often years assuming no withdrawals are made?
A. $8,416.32.
B. $8,872.93.
C. $9,251.82.
D. $9,549.11.

答案是C，下面是过程不过我没看懂。 不是说10年吗怎么给的答案加起来就8年啊？ 3年5% Interest Rate, 5年4% Interest Rate. 谁能解释一下啊谢谢了。

It to best to break this problem into parts to accommodate the change in the interest rate. Money in the
fund at the end of ten years based on deposits made with initial interest of 5%:
(1) The total value in the fund at the end of the fifth year is $3,152.50: PMT = $1,000; N = 3; I/Y = 5; CPT
→ FV = $3,152.50.
(2) The $3,152.50 is now the present value and will then grow at 4% until the end of the tenth
year. We get: PV = -3,152.50; N = 5; I/Y = 4; PMT = 1,000; CPT → FV = $9,251.82

minminmin

楼主可以画一个时间序列的图解这类的问题

这道题是从第三年开始Deposit money的，所以数轴上从第三年到第五年的计算，是步骤（1），算出第五年的value,然后步骤(2)是算出后五年的投资的future value，也即最后一年的终值