If you remove one from eleven, it becomes ten. If you remove one from nine, it becomes ten.

How is this possible?

There was a strange boy who was born before his father. How can this be possible?

A father is locked up in jail. His wife has gone bankrupt. Their male child has to sell his hotel in order to gain some money. Yet their girl child does not care and is quite happy.

How can someone be so rude?

John was piloting a plane behind a car but was never able to overtake it. Why?

Can you tell a 3D object that has just two surfaces?

As easy as you can get into me, it is as hard to get out of me.

Do you know what I am?

What do you see in the given picture?

What is the next number?

77, 49, 36, 18 ?

What does this say?

XLR8

There are people and strange monkeys on this island, and you can not tell who is who (Edit: until you understand what they said - see below). They speak either only the truth or only lies.
Who are the following two guys?
A: B is a lying monkey. I am human.
B: A is telling the truth.