A zero-coupon bond which will pay $1,000 in 10 years is selling
today for $422.41. What annual interest rate does the bond offer?

9% if I'm not mistaken.

Have a good day.

Very short answer, did not elaborate or offer an analysis...I realize
the payoff on this question is low, however, can pay more for a
greater effort

Guzman9,
A lot of your questions look like homework, which shouldn't be
answered on G-A.)  9% pa is correct.

Comments are free; only researchers get paid for their answers.

This is from the answer to a previous question of yours (Question ID:
445741) and is the formula which I used:

"Hi guzmanr9-ga,

Compounded interest follows a relatively straightforward formula:

P(1+r)^t

Where:
P = Principal amount
r = rate of return
t = time elapsed"

You know P, t and the final value so: 422.41(1+r)^10=1000.

Solve for r. 

Have a good day.

thither is completly right.. In a zero coupin bond .. you don't have
coupon ( which might complicate your life) .. you are left with
principal and the final return .. and all you have to do is use
compound interest formulae. ( Only in case where you don't want the
annual interest rate i.e not compounded annually will the formulae
different.. )