Independent solution

How to solve this Stepped and Level Perpetuities question

Setup

Setup

Let v be the annual discount factor. The first five payments occur at times zero through four because the contract is a perpetuity-due.

v=(1.07)1v=(1.07)^{-1}
Pt=350(1.03)t,0t4P_t=350(1.03)^t,\quad 0\le t\le4

Model

Model

After the fifth payment, the amount no longer grows. The remaining level perpetuity begins at time five with payment equal to the fifth payment.

X=t=04350(1.03)tvt+350(1.03)4v51vX=\sum_{t=0}^{4}350(1.03)^t v^t+350(1.03)^4\frac{v^5}{1-v}

Compute

Compute

The finite stepped portion and the discounted level tail are evaluated at time zero.

X=1,638.376+4,278.810X=1{,}638.376+4{,}278.810
X=5,917.186X=5{,}917.186

Answer

Answer

The price rounds to 5917, the amount in choice D.

X5,917(D)\boxed{X\approx5{,}917\quad\text{(D)}}