Answer:
5 hours and 40 minutes would be class
Explanation:
We know that the total time is 7 hours, which in minutes would be:
7 * 60 = 420
420 minutes would be class, now, we subtract the other times that are not to be in class and it would be:
420 - 30 - 50 = 340
So we could say that in class it takes 340 minutes, and if we spend hours it would be:
340/60 = 5.67 hours or also 5 hours and 40 minutes would be class.