Answer:
5.14%
Step-by-step explanation:
Determining the pretax cost of debt is the first to do prior to ascertaining after tax cost of debt.
Pretax cost of debt can be computed using the rate formula in excel.
=rate(nper,pmt,-pv,fv)
nper is the number of times the bond would coupon interest,hence paying coupon every six months for 20 years means 40 coupon payments
pmt is the semiannual coupon bondholders would received from the bond i.e $1000*7.25%*6/12=$36.25
pv is the current market price at $875
fv is the face value of $1000
=rate(40,36.25,-875,1000)=4.28% semiannually
=4.28% *2=8.56% annually
after tax cost of debt=8.56%*(1-t),where t is the tax rate of 40% or 0.40
after tax cost of debt=8.56%*(1-0.4)=5.14%