@GeniUs Right. A bank looking for smart people is not going to give a test that just asks you to divide 100 by 10 - a kid could do that. So the answer can't be 10, what could it be and why?

11 is the answer. After drinking the 10 glasses he's made he has 10 new lots of dregs to make it into an 11th glass.

I think it's a shit question but can see the point of it.

@JonUK41 I would argue there are too many other variables and a poor example of compound v basic interest to be a good question.
edit: Also risk analysis has to come into the equation.

@GeniUs Thinking 9 would be an acceptable answer. After drinking 9 he fell down drunk and/or threw up and couldn't drink any more.

The whole point of the question seems to be the answer is not 10.

@hippyjoe1955 Just edited the question to make clear - how many full glasses can he get from 100 glasses with dregs?

My fault for not phrasing it properly