A girl was sitting in her hotel room when she heard a knock on the door. She opened the door and found that a man was standing outside. The man said, "Oh! I am really sorry, I thought this was my room." He then walked through the corridor to the elevator. The girl did not know the man. She closed her door and called security asking them to apprehend the man. What made her suspicious of that man? He might have been genuinely mistaken.

The dirtier I get, the whiter I look. Who am I?

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?

John named his first son Alpha, second Beta, third Charlie and fourth Delta. What is the fifth son's name?

Prove that twice of ten is the same as twice of eleven.

who is silent in the parliament?

Replace the letters of words with a number so that the below equation holds true

BASE +
BALL
---------
GAMES
----------

Can you divide numbers from 1 to 9 (1 2 3 4 5 6 7 8 9) into two groups so that the sum of the numbers of each group is equal?

Note: 9 cannot be turned over to make it 6.

By moving exactly three matchsticks can you make the below equation true.It can be solved by 3 ways.

You have two buckets of 11 liters and 6 litres.
How can you measure exactly 8 litres?