I Just Got a Certificate of Achievement in French

I just took the Duolingo French exam (it's online and kind of free). It comprised of dictation and translation, which is a nice test of oral and literary skills in French. I don't think I got every question correct (the test took around 20 minutes), but I still got a perfect score of 5 out of 5. I even got a signature from Luis von Ahn, the CEO of Duolingo.

Some background information
Duolingo is an online platform for language learning. I have been learning French for a few years in high school and I wanted to test my abilities. Basically, I played the first level to accumulate enough in-gate currency (lingots) to buy one try on the exam, which I then took. I didn't think I would get a perfect score, but you never know...

Here is what the certificate looks like:


My last name is not Black. I don't know the deal about the decimals. A sigfig issue, perhaps?