Can you place six X (crosses) in below board without making three in a row in any way ?

What have one eye but still cannot see?

Can you find out the missing number?

? 4 5 3 5

9 5 7 10 3

I am the beginning of everything, the end of everywhere. I'm the beginning of eternity, the end of time and space. What am I?

If 2 workers can complete painting 2 walls in exactly 2 hours.

How many workers would be needed to paint 18 walls in 6 hours?

You enter your friend's room. He is not in his room. Although you see that on the bed there are two dogs, five cats, two giraffes and three pigs. Also, a couple of chickens and ducks are flying in the room.

Calculate the number of legs standing on the floor.

I cry without having a voice.
I fly without having wings.
I bite without having teeth.
I whisper without a mouth.

Who am I?

I am a type of room you cannot enter or leave. Raised from the ground below, I could be poisonous or a delicious treat. What am I?

Your mother’s brother’s only brother-in-law is asleep on your couch. Who is asleep on your couch?

A woman lives in a skyscraper thirty-six floors high and is served by several elevators which stop at each floor going up and down. Each morning she leaves her apartment and goes to one of the elevators. Whichever one she takes is three times more likely to be going up than down. Why?