I just did it quick and didn't think of the proration part of it, but unless your question is actually a little different that what you wrote here, it doesn't say 8% per year, so there was no way for me to know that....but you should have been told that if you were to get the problem done correctly! But the 360 is another accounting phenomenom....to make things easier.....yeah, right!

And yes, I think your professor has it backwards. When you said that was the answer you were given, I was totally confused too until I read through the whole thing and realized it was just backwards. Way to confuse the students prof!

Glad you basically had it right though and it was just the goofy answer from the prof that had you confused. See, you know more than you thought you knew!