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 beggar on the street can make one cigarette out of every 6 cigarette butts he finds. After one whole day of searching and checking public ashtrays the beggar finds a total of 72 cigarette butts. How many cigarettes can he make and smoke from the butts he found?

What jumps when it walks and sits when it stands?

You have two strings whose only known property is that when you light one end of either string it takes exactly one hour to burn. The rate at which the strings will burn is completely random and each string is different.

How do you measure 45 minutes?

You need to move three matchsticks to form three squares. Can you do it?

Can you count the number of matches in the picture below ?

I travel all around the world but always stay in the corner. What am I?

There is a box in which distinct numbered balls have been kept. You have to pick two balls randomly from the lot.

If someone is offering you a 2 to 1 odds that the numbers will be relatively prime, for example
If the balls you picked had the numbers 6 and 13, you lose $1.
If the balls you picked had the numbers 5 and 25, you win $2.

Will you accept that bet?

You may enter, but you may not come in. I have space, but no room. I have keys, but open no lock. What am I?

Which tank will fill first?