Independent solution

How to solve this Deposits Accumulated into a Semiannual Perpetuity question

Setup

Setup

Place the beginning-year deposits at times zero through four and accumulate each to time 10.

F10=100(1.13)10+100(1.13)9+150(1.13)8+150(1.13)7+150(1.13)6F_{10}=100(1.13)^{10}+100(1.13)^9+150(1.13)^8+150(1.13)^7+150(1.13)^6

Model

Model

The accumulated fund is 1703.8111.

F10=1,703.8111F_{10}=1{,}703.8111

Compute

Compute

Convert the annual effective yield to a half-year effective rate and price a perpetuity-immediate.

j=(1.12)1/21=0.05830052j=(1.12)^{1/2}-1=0.05830052
F10=XjF_{10}=\frac Xj

Answer

Answer

The semiannual payment is approximately 99, choice A.

X=1,703.8111(0.05830052)=99.3331X=1{,}703.8111(0.05830052)=99.3331
X99(A)\boxed{X\approx99\quad\text{(A)}}