There are 20 people in an empty, square room. Each person has full sight of the entire room and everyone in it without turning his head or body, or moving in any way (other than the eyes). Where can you place an apple so that all but one person can see it?

In a family supper, a grandfather, a grandmother, two fathers, two mothers, four children, three grandchildren, one brother, two sisters, two sons, two daughters, one daughter-in-law, and one mother-in-law need to sit at a table.

There are only seven chairs available at the place. How many more chairs do they have to borrow so that everyone can sit down together for the suppers if everybody requires a separate chair?

I am a prime number.
The double of myself is equal to the square of me.

which number am I?

There are two guys standing face to face in a room. On a wall, there is a clock. One of those is a prophet. He tells the other guy that he will be stabbed in the back in five minutes.

Shocked to hear that, the other guy stares at the clock. Just after the five minutes, he is stabbed on the back. Can you tell what happened?

Jack was having a candle light dinner with his girlfriend. Suddenly a cold gush of wind entered through the open window and three of the ten candles were extinguished. Assuming that none of the other candles were extinguished.

How many candles are they left with in the end ?

Quickly Solve this riddle

7 - 4 + 3 * 0 + 1 = ?

If a zookeeper had 100 pairs of animals in her zoo, and two pairs of babies are born for each one of the original animals, then (sadly) 23 animals don’t survive, how many animals do you have left in total?

Can you complete the sequence?

192, 021, 222, 324, 252, 627, 2__, 9__?

It's a protector.
It sits on a bridge.
One individual can see directly through it, while others wonder what it hides.

What is it?

I have holes on the top and bottom. I have holes on my left and on my right. And I have holes in the middle, yet I still hold water. What am I?