I know how to amortize a bond and complete and amortization schedule. I am just having a real tough time figuring out how to calculate the effective interest rate when it is not given. For example we did this problem in class

Harris Company sells 10% bonds having a maturity value of $2,000,000 for $1,855,816. The bonds are date Jan. 1, 2014 and mature Jan. 1,2019 Interest is payable annually on Jan.1 Set up a schedule of interest expense and discount amortization under the effective interest method.

I know it ends up being 12%, I just do not understand how we get that 12%. As a side note I am not allowed to use anything other than the tables and a basic four function calculator. (add, subtract, multiply, divide)

You do not need to complete the schedule if you can just show step by step directions on computing the effective interest rate that would be great and very much appreciated