If 21x = 79x, what is the value of x?

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?

What has six faces, but does not wear makeup, has twenty-one eyes, but cannot see? What is it?

Sherlock Holmes was challenged to make a pre-drawn line smaller without erasing it. He did it in fractions of seconds. How?

This was asked in an interview with Coa-Cola.

The interviewer has given me 100 marbles(50 white and 50 black) and two empty boxes.
He then told me that he will leave the room and i need to place all the marbles in two boxes.

And When he come back, he will draw a marble from any of the two box and if the marble is white I will be hired.

Also
* No box can be empty.
* All 100 marbles must be placed in one of the two boxes.

So what should I have done?

During which month do people sleep the least?

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?

In the given figure, you can see that four match sticks are used to form a square. Can you form five squares by using six matches?

What word is represented by this rebus?

Can you find the hidden animal in the picture below?