If mega corp. borrows $9,000 and agrees to pay the lender $10,500 in one year, the annual interest rate on this loan is approximately:

In simple interest, the interest rate is

i = (10500-9000) / 9000=16.67%

In compound interest, compounded monthly,

10500=9000 (1+i/12) ^12

=>

APR=12 (10500/9000) ^ (1/12) - 1

=11.155%

(effective interest is still 16.67%)