A seven-year-old kid challenged his classmates that he can make the number one disappear by adding something to it.

How can he do that?

I speak without a mouth, and hear without ears. I have no-body, but I come alive with the wind. What am I?

Can you make a six-letter word using the letters N, A and B ?

Find the next number in the sequence

5 12 24 36 ?

Three people enter a room and have a green or blue hat placed on their heads. They cannot see their own hat but can see the other hats.
The colour of each hat is purely random. They could all be green, blue, or any combination of green and blue.
They need to guess their own hat colour by writing it on a piece of paper, or they can write 'pass'.
They cannot communicate with each other in any way once the game starts. But they can have a strategy meeting before the game.
If at least one of them guesses correctly they win $10,000 each, but if anyone guesses incorrectly they all get nothing.
What is the best strategy?

I had an infinite supply of water and 5 litres and 3 litres jars.

How would you measure exactly 4 litres in the least number of steps?

What animal walks on four legs in the morning, two legs during the day, and three legs in the evening?

Oedipus, the king of Thebes, figured out the answer to the riddle:

You are playing as white and given four rooks to checkmate the black king in four moves with the following rules 1. You can place one rook every move and ensure the black king should be in check position.2. After four moves the black king should be in the checkmate position.

They came out at night, without being called.
They lost at day, without being stolen.
Who are they?

There are nine letters in the below-given diagram. You have to form a nine-letter word using these letters.