Independent solution

How to solve this Interest Rate Valuation question

Setup

Setup

Convert the nominal quarterly quote to its effective rate for one quarter.

1+iq=1+0.084=1.021+i_q=1+\frac{0.08}{4}=1.02

Model

Model

A quarter comprises three monthly payment periods, so three monthly accumulation factors must equal the quarterly factor.

(1+im)3=1.02(1+i_m)^3=1.02

Compute

Compute

Taking the positive cube root isolates the monthly effective rate.

im=(1.02)1/31i_m=(1.02)^{1/3}-1

Answer

Answer

The equivalent rate per monthly payment period is the expression in choice A.

im=(1+0.08/4)1/31(A)\boxed{i_m=(1+0.08/4)^{1/3}-1\quad\text{(A)}}