What has a ring but no finger?

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.

John was driving a bus and got stuck when passing through an underpass. Then came Jacob with a needle and got the bus out of the underpass.

What did the boy do?

It has horns but can’t beep. It is like to bleat but It is not a sheep. What is it?

When I get multiplied by any number, the sum of the figures in the product is always me. What am I?

Can you replace the question mark with the correct letter?

6 + 6 + 6 = N
7 + 7 + 7 = E
8 + 8 + 8 = R
0 + 0 + 0 = ?

Take away my first letter, then take away my second letter. Then take away the rest of my letters, yet I remain the same. What am I?

If we add four times the age of John four years from now to five times his age five years from now we get ten times his current age.

How old will John be two years from now?

Can you decipher the following common phrase?

T M C
A U O
H S M
W T E

Can you find out the number that should replace the question mark with a valid reason?