Can you replace the question mark with the correct number?

The pound is not a finish.

We are sharing a few instructions below, which you have to use in any suitable order to modify the above sentence such that the end sentence is a scientific fact.

- Eliminate a letter and supplement another in its place.
- Take away one word.
- Remove one letter from one word.
- Get rid of two letters from one word.
- Swap a word with its antonym.

Today, I celebrated my 32nd birthday but I was born in 1972.
How is this possible?

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.

There is a place where if I stand up straight, I will still be considered sideways.

Why is Saturday stronger than Monday?

Manish has to secure 40% marks to pass his B.tech final exams.
He got just 40 marks and failed by 40-marks.

What is the maximum marks?

There are two guys standing face to face in a room. On a wall, there is a clock. One of those is a prophet. He tells the other guy that he will be stabbed in the back in five minutes.

Shocked to hear that, the other guy stares at the clock. Just after the five minutes, he is stabbed on the back. Can you tell what happened?

Can you find the odd number in the following?

2716, 4135, 5321 and 7145

Find out the missing number in the picture attached: