If you say my name, I will no longer exist. What am I?

A pond had 60 fish, out of which, all but 20 died.
How many fishes are now present in that pond?

In a science lab, a petri dish hosts a healthy colony of yeast for an experiment. Now every minute, all the yeast cells divide into two. At noon, there was just a single cell of yeast and at 1:22, the Petri dish was half full. Can you calculate when the dish will be full of yeast?

Can you think of any three-dimensional shape that comprises of exactly two surfaces?

What can run but never walks, has a mouth but never talks, has a head but never weeps, has a bed but never sleeps?

Eight of us go fourth, not back, to protect our king from an attack. What are we?

The king of Octopuses has servants who have six, seven or eight legs. The distinguishing characteristics of the servants is that the one with seven legs always lie but the one with either six or eight legs speak the truth always.

One day, four servants meet and converse:

The black one says, 'We have 28 legs altogether.'

The green one says, 'We have 27 legs altogether.'

The yellow one says, 'We have 26 legs altogether.'

The red one says, 'We have 25 legs altogether.'


Can you identify the colour of the servant who is speaking the truth?

Look at the picture and find out which square is not linked with any of the other squares.

What has 88 keys?

Which is the rope you never skip with?