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Can you find out which number multiplied by itself will give the output as 12345678987654321?

What is black when you buy it, red when you use it, and gray when you throw it away?

Give it food and it will live; give it water and it will die.

Your last good ping-pong ball fell into a narrow metal pipe embedded one foot deep in concrete.
How can you get it out undamaged, if all the tools you have are your tennis paddle, shoe laces, and plastic water bottle, which does not fit into the pipe?

You have a thousand Re. 1 coins with you. You have ten bags with you and you can put any number of coins in each of the bags. The condition is that if someone asks you for any amount between 1 and 1000, you must be able to give that amount by just giving the bag (you are not allowed to open the bag and give coins).

How will you do it?

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

A man started to town with a fox, a goose, and a sack of corn. He came to a stream which he had to cross in a tiny boat. He could only take one across at a time. He could not leave the fox alone with the goose or the goose alone with the corn. How did he get them all safely over the stream?

What can run but never walk, have a mouth that never speaks, have a head that never weeps, and have a bed but never sleeps?

Can you count the number of children in the picture below