This Exam FM sample reference tests Bond Pricing and Yields. Per unit face, the combined price equals two discounted redemptions plus coupon rates rA and rA + 0.005 times the 30-year annuity factor. Solving the total price ratio 3 gives rA = 10.78%, choice B.
These notes identify the calculation error associated with each wrong letter when that error is reproducible.
AChoice A (10.06%) does not satisfy the combined price of both 30-year coupon and redemption streams at 7%; no distinct standard one-step error is identifiable.
CChoice C (10.90%) does not satisfy the combined price of both 30-year coupon and redemption streams at 7%; no distinct standard one-step error is identifiable.
DChoice D (11.31%) does not satisfy the combined price of both 30-year coupon and redemption streams at 7%; no distinct standard one-step error is identifiable.
EChoice E (11.84%) does not satisfy the combined price of both 30-year coupon and redemption streams at 7%; no distinct standard one-step error is identifiable.
Original practice · fully worked
Original variant: coupon-rate spread recovered from a two-bond total price
Two 30-year 1,000-face bonds both yield 7% annually. Bond A's coupon rate is 6%; Bond B's coupon rate is 6% plus an unknown spread s. Their combined price is 1875.91. Calculate s.
A 0.80%
B 0.85%
C 0.90%
D 0.95%
E 1.00%
Variant answer in brief
Subtracting the two known 6% coupon streams and both redemptions from the quoted total leaves s times the 30-year annuity factor. The spread is 1.00%, choice E.
Setup
Setup
Write the combined price at the common 7% yield.
P=1000[(0.06a30+v30)+((0.06+s)a30+v30)]
Model
Model
Remove both known redemption values and the two 6% coupon components.
1000sa30∣0.07=P−2000v30−120a30∣0.07
Compute
Compute
Solving gives spread 1.000000%.
s=0.0100000000
Answer
Answer
The coupon-rate spread is 1.00%, selecting choice E.
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