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?

An express train takes 3 seconds to enter the tunnel which is 1 km long.
If it is travelling at 120 km an hour, how long will it take to pass completely through the tunnel?

An evil man kidnapped someone and made them take one of two pills. One was harmless, but the other was poisonous. Whichever pill the victim took, the kidnapper took the other one. The victim took their pill with water and died. The kidnapper survived. How did the kidnapper get the harmless pill?

There's one "sport" in which neither the spectators nor the participants know the score or the leader until the contest ends.

What is it?

A cat had three kittens: Snophy, Topsy and Jorden. What was the mother's name?

I have a hole in my back and legs I lack.
I live where I can’t breathe and I eat without teeth.
What am I?

Count the number of triangles in the given picture.

2, 3, 5, 9, 17, _ What is the next number in the sequence?

There were two grandmothers and their two granddaughters.
There were two husbands and their two wives.
There were two fathers and their two daughters.
There were two mothers and their two sons.
There were two maidens and their two mothers.
There were two sisters and their two brothers.
Yet there are only six, who are buried here,
All are born legitimate and relationships clear.
How can this happen?

How can you make the following equation true by drawing only one straight line: 5+5+5=550 ?