Mazy's Muddle 15: Chalk & Cheese

My uncle is reading ‘The Book of General Ignorance’, and he says everything we think we know is probably wrong!

Do you know, the chalk we use to write on the blackboard is not chalk?  I believe the present day ‘chalk’ that Raghu Sir throws at us when we talk in class is made mostly of a substance called gypsum, widely available in nature, and made mostly of calcium sulphate.

Real chalk is made of calcium carbonate, the same thing that is found in coral and marble. If Raghu Sir  throws 23 pieces of gypsum chalk at us each day, and if he breaks a new chalk stick  into five bits, how many full-size, new chalk sticks would he need each day?

I got one on my head yesterday....must be the reason why I can’t find out the answer on my own. Help please!

Out of the maze:

If you answered 4 and three-fifths, you’re wrong, of course, since the question is about full-sized chalk. He would need five full-size sticks. And a bit would be left out. And he would need a few more to write on the board. So, correct answer, 5 or more.