Look at this sequence from top to bottom. What is the next number in the sequence?
1
11
21
1211
111221
312211

I am lying and I always lie. Tell me whether I am lying or telling the truth.

How many cubic feet of dirt are in a hole of one foot deep, three feet long, and two feet wide?

What does this rebus puzzle means ?

Can you find the missing letter in the sequence?
S - T - I - L - ? - T - F - Y - C

What's the only room from which no one can enter or leave

There was once a college that offered a class on probability applied to the real world. The class was relatively easy, but there was a catch. There were no homework assignments or tests, but there was a final exam that would have only one question on it. When everyone received the test paper it was a blank sheet of paper with a solitary question on it: 'What is the risk?'.Most students were able to pass, but only one student received 100% for the class! Even stranger was that he only wrote down one word!
What did he write?

What is the riddle which can be asked all day with a different correct answer each time.

There are are five things wrong with this sentence; only geniuses will be able to to spot all of the mitstakes

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?