I teach high school algebra and we have 55 minute classes.
Here is a typical day for me.
5 minutes to take roll and enter in computer.
5 minutes to call out answers so students can grade papers.
5 minutes on any questions over home work.
5 minutes to go over quiz from the day before.
10-15 minutes to take a quiz.
15-30 minutes to teach lesson for the day. Typically 20 minutes.
Now I do not always have a quiz to give or go over. So some days I have that 15-20 minutes extra.
So that leaves anywhere form 10 to 30 minutes for the students to work on the days lesson in class. Usually they have 15 minutes to work.
I have a average of 22 students in each class. Which is pretty good. Like I said I usually have 15 minutes for the kids to work in class so that gives less than one minute for me to help each student one on one.
I could go on and on about the day and the kinds of students but I would get to long so I will stop.