You aare considering buying a new $25,000 car. The car dealer offers you a 13.6% loan with 30 equal monthly payments. Upon the questioning the dealer, you find that this unusual loan has "add-on" interest, so that an interest charge of $8,500 (13.6% x $25,000 x 2.5 years) is added on to the $25,000 for a total amount to be repaid of $33,500. The payments are $1,116.67 each month ($33,500/30)
What is the approximate effective annual interest rate of this loan?