An infinite number of mathematicians are standing behind a bar. The first asks the barman for half a pint of beer, the second for a quarter pint, the third an eighth, and so on. How many pints of beer will the barman need to fulfill all mathematicians' wishes?

How many triangles are there on the puzzle below?

What three numbers, none of which is zero, give the same result whether they’re added or multiplied?

Can you find out the missing number in the grid?

What does a man do only once in his lifetime, but women do once a year after they are 29?

Which number should replace the question mark?

It is deaf, Dumb and Blind!!!

Still, always tells the truth. What is it?

What is the longest word in the dictionary?

A King wants to send the diamond ring to his girlfriend securely. He got multiple locks and their corresponding keys. His girlfriend does not have any keys to these locks and if he sends the key without a lock, the key can be copied in the way. How can King send the ring to his girlfriend securely?

There are three Athletes (John, Tarun and Harish) and their individual Coaches (Jacob, Meenaxi and Priyanka) standing on the shore.
No Coach trusts their Athlete to be near any other Coach unless they are also with them.
There is a boat that can hold a maximum of two persons.
How can the six people get across the river?