When 99 is considered higher than 100?

10 people came into a hotel with 9 rooms and each guest wanted his own room. The bellboy solved this problem.
He asked the tenth guest to wait for a little with the first guest in room number 1. So in the first room, there were two people. The bellboy took the third guest to room number 2, the fourth to number 3, ..., and the ninth guest to room number 8. Then he returned to room number 1 and took the tenth guest to room number 9, still vacant.
How can everybody have his own room?

P is the father of Q and S is the son of R. T is the brother of P and has a daughter U. If R is the sister of P, then what is the relation between U, Q and S?

You bought me for dinner but never eat me. What am I?

What does the following represent?

N N N N N N N

A A A A A A A

C C C C C C C

What brings you down but never up?

With pointed fangs I sit and wait; with piercing force I crunch out fate; grabbing victims, proclaiming might; physically joining with a single bite. What am I?

A man who was outside in the rain without an umbrella or hat didn’t get a single hair on his head wet. Why?

I have a head like a cat and feet like a cat, but I am not a cat. What am I?

You need to move three matchsticks to form three squares. Can you do it?