Independent solution

How to solve this Spot and Forward Rates question

Setup

Setup

Convert annual accumulation to fractional-year discounting and record each mid-month charge at time n minus one-half months.

PVcharges=n=11579.99(1.168)(n0.5)/12PV_{\mathrm{charges}}=\sum_{n=1}^{15}\frac{79.99}{(1.168)^{(n-0.5)/12}}

Model

Model

Record each payment at month-end and treat the final balance as an additional payoff at month 15.

PVout=n=115250(1.168)n/12+3000(1.168)15/12PV_{\mathrm{out}}=\sum_{n=1}^{15}\frac{250}{(1.168)^{n/12}}+\frac{3000}{(1.168)^{15/12}}

Compute

Compute

Set opening balance plus charges equal to all payments and the terminal payoff.

X+PVcharges=PVoutX+PV_{\mathrm{charges}}=PV_{\mathrm{out}}

Answer

Answer

This timing and exponent structure is the equation in choice E.

choice E\boxed{\text{choice E}}