Though the tactic of asking tough riddles during interviews has dissipated lately, the amazement of people on the internet has grown. Along with this so has the popularity of sharing and solving these tough questions has risen as well.

So do you think you have what it takes to do what some of the top geniuses at Google, and Microsoft have done by solving these tricky brain teasers? Do your best; this group is here for the taking.

This collection is here for the sharing too, don't be shy to challenge a friend or two with these intriguing puzzles.

## Solitary Confinement Riddle

You are in solitary confinement. It is Friday afternoon and you absolutely must have a cigarette. The only person who can give you one is the guard outside your cell. What do you do?

Hint:

To get the guard to give you a cigarette (and this really is the preferred answer to this question), threaten to kill yourself by smashing your head against the wall of your cell. That gives you leverage with the guard - hed be tied up by doing paperwork about your suicide, so hed miss weekend time with his family (its Friday afternoon, remember?) -- so hell give you a cigarette.

YES NO

*Did you answer this riddle correctly?*YES NO

## The Non Digital Clock Riddle

Calculate the number of degrees between the hour hand and the minute hand of a clock (nondigital) that reads 3:15.

Hint:

The hour hand will have moved one-fourth of an hour; therefore, there will be 7.5 degrees between the two hands.

YES NO

*Did you answer this riddle correctly?*YES NO

## The Center Of A Rubiks Cube

Hint:

## Black Socks Riddle

You wake up one morning and theres been a power outage. You know you have 12 black socks and 8 blue ones. How many socks do you need to pull out before youve got a match?

Hint:

## 3 Envelops Riddle

You are sitting in front of your interviewer. He gives you three envelopes. One of them contains an offer letter and the other two are empty. You pick up one of them. Now, the interviewer opens up one of the envelope lying on the table and you find out that it is blank.

Now, he gives you a chance to switch your envelope with the one on the table. Would you switch it? Why or why not?

Now, he gives you a chance to switch your envelope with the one on the table. Would you switch it? Why or why not?

Hint:

Yes, you should switch the envelope. In the beginning when you picked up the envelope, you had a 1/3 probability of finding an offer letter in the envelope. There was 2/3 chance that the letter was there in the two envelopes on the table.

If you keep your selected envelope, you still have a 1/3 chance of finding an offer letter in that. However, since the interviewer has removed one empty envelope from the table, if you switch, you have a probability of 2/3 that the offer letter is inside that.

YES NO

If you keep your selected envelope, you still have a 1/3 chance of finding an offer letter in that. However, since the interviewer has removed one empty envelope from the table, if you switch, you have a probability of 2/3 that the offer letter is inside that.

*Did you answer this riddle correctly?*YES NO

## Losing A New York Bet

You are hanging around in NYC when a person approaches you.

"Leaving the bald people aside, I can bet a hundred bucks that there are two people living in NYC who have same number of hairs on their heads," he says to you.

You say that you will take the bet. After talking to the man for a couple of minutes, you realize that you have lost the bet.

What did the person say to you that proved his statement ?

"Leaving the bald people aside, I can bet a hundred bucks that there are two people living in NYC who have same number of hairs on their heads," he says to you.

You say that you will take the bet. After talking to the man for a couple of minutes, you realize that you have lost the bet.

What did the person say to you that proved his statement ?

Hint:

This problem can be best solved using the pigeonhole principle.

The argument will go like this:

Assume that all the non-bald people in NYC have different number of hairs on their head. The population is about 9 million and let us assume that there are 8 million among them who are not bald.

Now, those 8 million people need to have different number of hairs. On an average, people have just 100, 000 hairs on their head. If we keep on assuming that there is someone with just one hair, someone with two, someone with three and so on, there will be 7, 900, 00 other people left who will have more than 100, 000 hairs on their head and need different number of hairs.

Now, as per this assumption, if we keep increasing one hair for each person, to make everybody hair different in numbers, we will come across someone with 8, 000, 000 hairs. But that is practically impossible (even 1, 000, 000 is impossible). Thus there must be two people who are having same number of hairs.

YES NO

The argument will go like this:

Assume that all the non-bald people in NYC have different number of hairs on their head. The population is about 9 million and let us assume that there are 8 million among them who are not bald.

Now, those 8 million people need to have different number of hairs. On an average, people have just 100, 000 hairs on their head. If we keep on assuming that there is someone with just one hair, someone with two, someone with three and so on, there will be 7, 900, 00 other people left who will have more than 100, 000 hairs on their head and need different number of hairs.

Now, as per this assumption, if we keep increasing one hair for each person, to make everybody hair different in numbers, we will come across someone with 8, 000, 000 hairs. But that is practically impossible (even 1, 000, 000 is impossible). Thus there must be two people who are having same number of hairs.

*Did you answer this riddle correctly?*YES NO

## BDay Bash Riddle

I engaged in a strange activity. My birthday was approaching and I decided to collect money for my birthday bash. On the first day of the month, I kept a dollar in my piggy bank, on the second, I kept two dollars and on the third, I kept three and so on.

On my birthday, I had a total of 276 dollars in my piggy bank. Can you find out on which day of the month was my birthday?

On my birthday, I had a total of 276 dollars in my piggy bank. Can you find out on which day of the month was my birthday?

Hint:

23rd.

The easiest way to find out without engaging in any formula would be to simply add them:

1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 + 11 + 12 + 13 + 14 + 15 + 16 + 17 + 18 + 19 + 20 + 21 + 22 + 23 = 276

YES NO

The easiest way to find out without engaging in any formula would be to simply add them:

1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 + 11 + 12 + 13 + 14 + 15 + 16 + 17 + 18 + 19 + 20 + 21 + 22 + 23 = 276

*Did you answer this riddle correctly?*YES NO

## 10 Boxes Riddle

There are ten boxes containing some balls. Each of the ball weighs exactly 10 grams. One of those boxes have defective balls (all the defective balls weigh 9 grams each).

An electronic weighing machine is provided to you and you are allowed only one chance of weighing on it.

How will you find out which box has defective balls ?

An electronic weighing machine is provided to you and you are allowed only one chance of weighing on it.

How will you find out which box has defective balls ?

Hint:

Let us simplify boxes by naming them from 1 to 10.

Now the trick here is to pick different number of balls from different boxes. So to simplify things, we will pick balls corresponding to box number.

Thus, pick 1 ball from Box 1, 2 balls from box 2, 3 balls from box 3 and so on. You will have 55 balls altogether. Now, put them all in the balance.

If all balls were weighing accurate 10 grams, the total weight of the 55 balls would have been 550 grams. But one of the box must have had the defective balls.

Suppose if the defective balls were in box number 2, then the total weight will be 2 grams less than 550. If the defective balls were in box 8, the total weight will be less than 8 grams from 550. In this way, you will be able to identify which box has the defective balls.

YES NO

Now the trick here is to pick different number of balls from different boxes. So to simplify things, we will pick balls corresponding to box number.

Thus, pick 1 ball from Box 1, 2 balls from box 2, 3 balls from box 3 and so on. You will have 55 balls altogether. Now, put them all in the balance.

If all balls were weighing accurate 10 grams, the total weight of the 55 balls would have been 550 grams. But one of the box must have had the defective balls.

Suppose if the defective balls were in box number 2, then the total weight will be 2 grams less than 550. If the defective balls were in box 8, the total weight will be less than 8 grams from 550. In this way, you will be able to identify which box has the defective balls.

*Did you answer this riddle correctly?*YES NO

## 2 Burning Candles

There are two candles. Both will only burn exactly for an hour. How will you use these two candles to measure forty-five minutes?

Hint:

Burn one candle from both the ends and simultaneously burn the other candle from just one end. In half an hour, the first candle would have been burnt fully and the second one would have been burnt half. Now light the other end of the second candle as well. In this way, the second candle will take only half the time (30/2 = 15) to burn fully.

Thus, you will have measured forty five minutes.

YES NO

Thus, you will have measured forty five minutes.

*Did you answer this riddle correctly?*YES NO

## On A Hiking Trip Riddle

Thirty friends were on a hiking trip when they decided to enjoy the bonfire. They assembled for it and agreed to play a game. For that, they divided themselves in five teams with seven members each, forming five rows.

How did they manage to achieve this formation ?

How did they manage to achieve this formation ?

Hint:

You can see that they decided to form a pentagonal formation.

YES NO

*Did you answer this riddle correctly?*YES NO

## Post Your Interview Riddles Below

Can you come up with a cool, funny or clever Interview Riddles of your own? Post it below (without the answer) to see if you can stump our users.