Translation:How many people are there in our class in total?
It doesn't sound unnatural to me in Australian English, maybe just a bit more emphatic with it than without it. Like just in case some people are not in the class today for some reason, you would still want the full number counting all the registered students, present or not.
This has got to be the worst lesson yet, it is absurd. Far too many weird questions, far too many characters to integrate, far too much danger in answering the question perfectly how they want. I wrote down every answer in Chinese, pinyin and English for the 4 lessons at level one, and yet the questions they are now asking in level 2 are still completely new.
There are some great things with this course but modern and effective educational methods seem to escape their capabilities. It's far to 'old school'.
How many people are in our class besides the ones Duo doesn't wish us to acknowledge? You know. Just because. I think I am learning the name of the algorithm Duo is employing in this course; Death by a thousand useless snippets.