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

What does this mathematical rebus means ?

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

After undergoing a successful eye operation, A blind girl has just boarded a train to her home. The doctor asked her to open the bandages after 3 hours. On her train journey, she opened the bandages and within a fraction of the time she commits suicide by jumping off the train.

Though her operation was successful, Why did she commit suicide?

If,
9 * 8 * 7 = 65
8 * 7 * 6 = 50
7 * 6 * 5 = 37

Find
6 * 5 * 4 = ?

I am the one who remains awake when you sleep. But I need to rest when you awake. Who Am I?

You see a mathematical expression in the picture. Can you think of a movie that this expression refers to?

If eleven plus two equals one, what does nine plus five equal?

Below the four parts have been reorganised. The four partitions are exactly the same in both arrangements. Why is there a hole?

The host of a game show offers the guest a choice of three doors. Behind one is an expensive car, but behind the other two are goats.
After you have chosen one door, he reveals one of the other two doors behind which is a goat (he wouldn't reveal a car).

Now he gives you the chance to switch to the other unrevealed door or stay at your initial choice. You will then get what is behind that door.

You cannot hear the goats from behind the doors, or in any way know which door has the prize.

Should you stay, or switch, or doesn't it matter?