Independent solution

How to solve this Exact Cash-Flow Matching with Coupon Bonds question

Setup

Setup

Let a, b, and c be the face amounts invested in the one-, three-, and four-year bonds.

1.07c=7,8111.07c=7{,}811

Model

Model

The last liability gives c, and the year-3 liability then determines b.

c=7,300c=7{,}300
1.05b+0.07c=15,4211.05b+0.07c=15{,}421
b=14,200b=14{,}200

Compute

Compute

Only coupons from Bonds B and C are available at year 2.

X=0.05b+0.07cX=0.05b+0.07c

Answer

Answer

Substitution gives 1221, choice A.

X=0.05(14,200)+0.07(7,300)=1,221X=0.05(14{,}200)+0.07(7{,}300)=1{,}221
X=1,221(A)\boxed{X=1{,}221\quad\text{(A)}}