I have one of the three numbers: 1, 2, or 3 in my mind. I speak only truth. You can ask me just one question for which I will only reply in yes or no or don't know. What question will you ask from me so that you are able to know the number?
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.