A chess tournament is taking place on knock-out terms (the one who loses the match is out of the game).
(a) If 10 matches are played in total, how many players participated?
(b) If 20 players took part in the tournament, how many matches were played?

what does the below rebus means?

There are 2 sand hourglasses.

The small one can measure 5 hours and the large one can measure 7 hours.

How can we measure 16 hours with 2 sand hourglasses running together ?

A mile-long train is moving at sixty miles an hour when it reaches a mile-long tunnel. How long does it take the entire train to pass through the tunnel?

Do you know of a place where the wind blows south and then suddenly shifts direction towards the north?

Can you find out the missing number?

? 4 5 3 5

9 5 7 10 3

In this image, you can see three almost identical Doraemon images. Can you spot the odd one out from them?

This is a classy optical illusion puzzle. What more you can find except bricks in the image below?

People make me, save me, change me, raise me. What am I?

In an interview, a boy was asked an unusual question 'How two persons sitting with a table in between them can't see each other?' He was unable to reply. Can you?