What is a word made up of 4 letters, yet is also made up of 3. Sometimes is written with 9 letters, and then with 4. Rarely consists of 6, and never is written with 5.

John is asked to stand behind Jacob and Jacob is asked to stand behind John. Both of them feel confused about it and don't know what to do?

But it is quite possible, do you know how?

There’s a one-story house in which everything is yellow. Yellow walls, yellow doors, yellow furniture. What colour are the stairs?

How can you spell "White of an egg" in one word?
Hint: I know you can spell coke, poke, and joke.

There was an aeroplane crash, every single person died, but two people survived. How is this possible?

You’re out on the water and see a boat filled with people. You look away for a second and look back again, but this time you don’t see a single person on the boat. Why? Hint: The boat did not sink.

A boy and a girl are sitting on the porch.
"I'm a boy," says the child with black hair.
"I'm a girl," says the child with red hair.
If at least one of them is lying, who is which?

No one wants to have it, but if one got it, he does not want to lose it. What is It?

I was speeding and ran through a stop sign, yet two traffic officers who were there do nothing about it.

why?

Can you convert the number zero(0) into a positive number using just one mathematical operator ?