I Don't Get It

Today I got my Japanese results back for the term. In the tests I got a C-, C-, C+, C+, D+ and a C. And then today I did a speaking test and I got a B which counts to 1/8 of my mark.

Then she told me that I'll be getting a B overall for the term which makes no sense at all because I worked it out to be a C!

Ohh well!

Yay for me!