How can a man go eight days without sleep?

I am an odd number. Take away a letter and I become even. What number am I?

You are presented with three boxes. One of them has a red ball inside and the other two have a black ball inside each of them. You are asked to pick up the one with red ball and you pick one. Now, one of the other boxes is opened and it is found to have a black ball.

You are presented with a chance to change your box with the one that is left closed. Will you change your box? Why or why not?

Why do you find that most of the buildings are deprived of the 13th floor?

When can we add 2 to 11 and get 1 as the correct answer?

What can go up a chimney down, but can’t go down a chimney up?

In the given figure, move three matchsticks so that the resulting figure contains two rectangles.

When I get multiplied by any number, the sum of the figures in the product is always me. What am I?

A plane crashed between the border of Mexico and America. Where do you bury the survivors?

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.