I'm having trouble getting the right answer on my homework. I keep getting an answer that seems right to me but the system keeps telling me it's wrong. The question is: "Determine the annual net cost of these checking accounts. A "-" sign must precede any negative net cost answers. Round your intermediate calculations to two decimal places." Annual interest of 2.5% paid if balance exceeds $900, $6 monthly fee if account falls below minimum balance, average monthly balance $990, account falls below $900 during 6 months. Round the answer to the nearest cent. I've put -11.25 and it is incorrect.

Nevermind, I figured it out.