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?

In 1990, a person is 15 years old. In 1995, that same person is 10 years old. How can this be?

Can you divide the below-given shape into four equal and identical pieces?

I have branches, but no fruit, trunk or leaves. What am I?

Can you find the six hidden animals in the picture below?

John enters a small room. The Door Closes.
When the door opens, John is in a larger room.

Explain?

Peter wakes up daily to pick up his cycle and crosses the border between Spain and France daily with a bag on his shoulder. He is investigated daily by the officials but they don't find anything suspicious.

If we tell you that he is smuggling something what would it be?

Can you find out the missing number?

? 4 5 3 5

9 5 7 10 3

Can you write down eight eights so that they add up to one thousand?

What can go up a chimney down, but can’t go down a chimney up?