B is correct.
The payments are 24 quarterly payments of $250 at the end of each quarter, and the 8% is quoted as an EFFECTIVE ANNUAL rate. The rate must therefore be converted geometrically to a quarterly effective rate before any annuity factor is used.
Convert the rate:
j=(1.08)1/4โ1=1.0194265โ1=0.0194265Count the payments:
n=6ร4=24.
Discount factor over the full term:
(1+j)24=(1.08)6=1.586874v24=1.5868741โ=0.630170Annuity-immediate factor:
a24โฃjโ=j1โv24โ=0.01942651โ0.630170โ=0.01942650.369830โ=19.03737Present value:
PV=250โ
a24โฃjโ=250ร19.03737=4,759.34Check with the m-thly annuity form. The quarterly payments total $1,000 per year, and
i(4)=4[(1.08)1/4โ1]=4(0.0194265)=0.0777062a6โฃ0.08โ=0.081โ(1.08)โ6โ=0.080.369830โ=4.622880PV=1,000โ
a6โฃ0.08(4)โ=1,000โ
i(4)iโโ
a6โฃ0.08โ=1,000ร0.07770620.08โร4.622880=4,759.34Both routes give
PVโ4,759, so the answer is B.
Traps to avoid. Setting the quarterly rate to
0.08/4=0.02 instead of taking the fourth root gives
250รa24โฃ0.02โ=4,728. Valuing $1,000 once a year with no m-thly adjustment gives
1,000รa6โฃ0.08โ=4,623, which prices annual rather than quarterly cash flows. Using an annuity-due factor gives
1,000รaยจ6โฃ0.08โ=4,993, stretching the term to seven years gives
5,206, and accumulating instead of discounting gives
1,000รs6โฃ0.08โ=7,336.