Independent solution

How to solve this Two-Phase Deposit Accumulation question

Setup

Setup

The quarterly yield is 1.25%. Separate the level first five years from the geometrically increasing final fifteen years.

j=0.05/4=0.0125j=0.05/4=0.0125

Model

Model

Accumulate the twenty beginning-quarter deposits at time 5 and then for sixty more quarters. Index the later deposits from k = 1 through 60.

S1=1,000s¨20j(1+j)60S_1=1{,}000\ddot s_{\overline{20}|j}(1+j)^{60}
S2=k=1601,000(1.02)k(1+j)61kS_2=\sum_{k=1}^{60}1{,}000(1.02)^k(1+j)^{61-k}

Compute

Compute

The two accumulated components are 48138.59 and 161639.07.

S1=48,138.591S_1=48{,}138.591
S2=161,639.068S_2=161{,}639.068
S1+S2=209,777.659S_1+S_2=209{,}777.659

Answer

Answer

The time-20 fund rounds to 209778, choice E.

209,778(E)\boxed{209{,}778\quad\text{(E)}}