A man has a barrel filled with oil that weighs 100 pounds, and then he puts something into it. Now the barrel weighs less than 100 pounds. What did he put in the barrel?

Can you name four days which start with the letter 'T'?

A number can be multiplied by multiple of nine
i.e 9 18 27 36 45 ...

and the resulting number consist of only one digit.

Can you identify the number ?

One is to three as three is to five and five is to four and four is the magic number.
What is the pattern?

Take one out and scratch my head, I am now black but once was red. What am I?

Can you solve this amazing hard number series problem?
7, 8, 10, 12, 16, 18 ?

I possess a head

I flaunt a tail

But I don't have mouth or legs

Can you find out who I am?

What word does this rebus represent?

meta meta
meta meta

In the city of Brain Teasers, 5% of people do not list their phone numbers. Now if we select random 100 people from the phone directory, then how many people selected will have unlisted phone numbers?

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?