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.

Below the four parts have been reorganised. The four partitions are exactly the same in both arrangements. Why is there a hole?

Can you calculate the probability of getting a sum of six when a dice is thrown twice?

In two decks of cards, what is the least amount of cards you must take to be *guaranteed* at least one four-of-a-kind?

The square root of number 121 is "11". What is the square root of the number "12345678987654321."?

What has hands, but can’t clap?

The peacock is a bird that does not lay eggs. How do they get baby peacocks?

Place a mathematical symbol between the numerals 5 and 9 in such a way that the resulting number is greater than 5 but smaller than 9.

I am a seven-letter word but if you remove four of my letters I will have one left. What word am I?

what's the probability of getting a king or a queen from a pack of 52 cards?