What does the following represent?

N N N N N N N

A A A A A A A

C C C C C C C

A chess tournament is taking place on knock-out terms (the one who loses the match is out of the game).
(a) If 10 matches are played in total, how many players participated?
(b) If 20 players took part in the tournament, how many matches were played?

How can you leave a room with two legs and return with six legs?

Can you find out the missing number?

? 4 5 3 5

9 5 7 10 3

What do you answer even though it never asks you questions?

Until it is measured, not known. Yet how you miss it when it has gone. What is it?

Two old friends, Jack and Bill, meet after a long time.

Three kids
Jack: Hey, how are you, man?
Bill: Not bad, got married and I have three kids now.
Jack: That's awesome. How old are they?
Bill: The product of their ages is 72 and the sum of their ages is the same as your birth date.
Jack: Cool..But I still don't know.
Bill: My eldest kid just started taking piano lessons.
Jack: Oh, now I get it.

How old are Bill's kids?

A girl says this to her best friend: “I was born in 1955, and I celebrated my 17th birthday last weekend.” Her best friend thinks she’s lying, but she’s actually correct. How is that possible?

What does this simple rebus mean?

It is deaf, Dumb and Blind!!!

Still, always tells the truth. What is it?