One Big Family Riddle
Four people are sitting around a campfire after a long day of recreation, when one man comments: "Do you realize that around this campfire, the four of us include a mother, father, brother, sister, son, daughter, niece, nephew, aunt, uncle and a couple cousins"?. If everyone is related by blood (with no unusual marriages) how is this possible?
Hint:
The campfire circle includes a woman and her brother. The woman's daughter and the man's son are also present. Did you answer this riddle correctly?
YES NO
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. Did you answer this riddle correctly?
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
A Rickety Bridge Riddle
Four people need to cross a rickety bridge at night. Unfortunately, they have only one torch and the bridge is too dangerous to cross without one. The bridge is only strong enough to support two people at a time. Not all people take the same time to cross the bridge. Times for each person: 1 min, 2 mins, 7 mins and 10 mins. What is the shortest time needed for all four of them to cross the bridge?
Hint:
17 mins.
The initial solution most people will think of is to use the fastest person as an usher to guide everyone across. How long would that take? 10 + 1 + 7 + 1 + 2 = 21 mins. Is that it? No. That would make this question too simple even as a warm up question.
Let's brainstorm a little further. To reduce the amount of time, we should find a way for 10 and 7 to go together. If they cross together, then we need one of them to come back to get the others. That would not be ideal. How do we get around that? Maybe we can have 1 waiting on the other side to bring the torch back. Ahaa, we are getting closer. The fastest way to get 1 across and be back is to use 2 to usher 1 across. So let's put all this together.
1 and 2 go cross
2 comes back
7 and 10 go across
1 comes back
1 and 2 go across (done)
Total time = 2 + 2 + 10 + 1 + 2 = 17 mins Did you answer this riddle correctly?
YES NO
The initial solution most people will think of is to use the fastest person as an usher to guide everyone across. How long would that take? 10 + 1 + 7 + 1 + 2 = 21 mins. Is that it? No. That would make this question too simple even as a warm up question.
Let's brainstorm a little further. To reduce the amount of time, we should find a way for 10 and 7 to go together. If they cross together, then we need one of them to come back to get the others. That would not be ideal. How do we get around that? Maybe we can have 1 waiting on the other side to bring the torch back. Ahaa, we are getting closer. The fastest way to get 1 across and be back is to use 2 to usher 1 across. So let's put all this together.
1 and 2 go cross
2 comes back
7 and 10 go across
1 comes back
1 and 2 go across (done)
Total time = 2 + 2 + 10 + 1 + 2 = 17 mins Did you answer this riddle correctly?
YES NO
Crossing The Bridge Riddle
There are two villages separated with a river. Each day, four people cross the river through a bridge to work on the other side and earn for their families. On one night when they were returning from work, they noticed that the bridge was about to collapse. Now all of them wanted to cross the bridge before it collapsed as no one wanted to be stuck on that end without their families.
They had just one torch with them and since it was the night time, they could not see without it. The bridge had become weak and it could only accommodate two people at a time. It was going to collapse in just 17 minutes.
The four people took different times to cross the bridge. First one took only a minute, second one took 2 minutes, third one took 5 minutes and the last one took 10 minutes.
How would all of them have managed to cross the bridge in time?
They had just one torch with them and since it was the night time, they could not see without it. The bridge had become weak and it could only accommodate two people at a time. It was going to collapse in just 17 minutes.
The four people took different times to cross the bridge. First one took only a minute, second one took 2 minutes, third one took 5 minutes and the last one took 10 minutes.
How would all of them have managed to cross the bridge in time?
Hint:
Let us denote the four people with A, B, C and D.
A takes 1 minute to cross, B takes 2, C takes 5 and D takes 10.
A and B cross first spending 2 minutes.
A comes back with torch taking 1 minute.
C and D cross taking 10 minutes.
B comes back with torch taking 2 minutes.
Finally, A and B cross the bridge taking 2 minutes.
2 + 1 + 10 + 2 + 2 = 17 minutes
Thus, this is the way they all managed to cross that bridge that night. Did you answer this riddle correctly?
YES NO
A takes 1 minute to cross, B takes 2, C takes 5 and D takes 10.
A and B cross first spending 2 minutes.
A comes back with torch taking 1 minute.
C and D cross taking 10 minutes.
B comes back with torch taking 2 minutes.
Finally, A and B cross the bridge taking 2 minutes.
2 + 1 + 10 + 2 + 2 = 17 minutes
Thus, this is the way they all managed to cross that bridge that night. Did you answer this riddle correctly?
YES NO
Old Bananas Riddle
Hint:
Just Like People Riddle
We are just like people.
We grow, we get old, we die off.
We come in many different colors.
Black, white, brown.
We come in a army, there are thousands of us, yet we have no war.
But we will still die off over the years.
What am I?
We grow, we get old, we die off.
We come in many different colors.
Black, white, brown.
We come in a army, there are thousands of us, yet we have no war.
But we will still die off over the years.
What am I?
Hint:
Bruce Wayne Is This Type Of Man
Its black, furry and flies about
Try not to be scared if you can
It likes to hang out upside down
And Bruce Wayne is this type of man
Who am I?
Try not to be scared if you can
It likes to hang out upside down
And Bruce Wayne is this type of man
Who am I?
Hint:
The Same Birthday Riddle
How many people must be gathered together in a room, before you can be certain that there is a greater than 50/50 chance that at least two of them have the same birthday?
Hint:
Only twenty-three people need be in the room, a surprisingly small number. The probability that there will not be two matching birthdays is then, ignoring leap years, 365x364x363x...x343/365 over 23 which is approximately 0.493. this is less than half, and therefore the probability that a pair occurs is greater than 50-50. With as few as fourteen people in the room the chances are better than 50-50 that a pair will have birthdays on the same day or on consecutive days. Did you answer this riddle correctly?
YES NO
YES NO
Three People In A Room
Three people enter a room and have a green or blue hat placed on their head. They cannot see their own hat, but can see the other hats.
The color of each hat is purely random. They could all be green, or blue, or any combination of green and blue.
They need to guess their own hat color by writing it on a piece of paper, or they can write 'pass'.
They cannot communicate with each other in any way once the game starts. But they can have a strategy meeting before the game.
If at least one of them guesses correctly they win $50,000 each, but if anyone guess incorrectly they all get nothing.
What is the best strategy?
The color of each hat is purely random. They could all be green, or blue, or any combination of green and blue.
They need to guess their own hat color by writing it on a piece of paper, or they can write 'pass'.
They cannot communicate with each other in any way once the game starts. But they can have a strategy meeting before the game.
If at least one of them guesses correctly they win $50,000 each, but if anyone guess incorrectly they all get nothing.
What is the best strategy?
Hint:
Simple strategy: Elect one person to be the guesser, the other two pass. The guesser chooses randomly 'green' or 'blue'. This gives them a 50% chance of winning.
Better strategy: If you see two blue or two green hats, then write down the opposite color, otherwise write down 'pass'.
It works like this ('-' means 'pass'):
Hats: GGG, Guess: BBB, Result: Lose
Hats: GGB, Guess: --B, Result: Win
Hats: GBG, Guess: -B-, Result: Win
Hats: GBB, Guess: G--, Result: Win
Hats: BGG, Guess: B--, Result: Win
Hats: BGB, Guess: -G-, Result: Win
Hats: BBG, Guess: --G, Result: Win
Hats: BBB, Guess: GGG, Result: Lose
Result: 75% chance of winning! Did you answer this riddle correctly?
YES NO
Better strategy: If you see two blue or two green hats, then write down the opposite color, otherwise write down 'pass'.
It works like this ('-' means 'pass'):
Hats: GGG, Guess: BBB, Result: Lose
Hats: GGB, Guess: --B, Result: Win
Hats: GBG, Guess: -B-, Result: Win
Hats: GBB, Guess: G--, Result: Win
Hats: BGG, Guess: B--, Result: Win
Hats: BGB, Guess: -G-, Result: Win
Hats: BBG, Guess: --G, Result: Win
Hats: BBB, Guess: GGG, Result: Lose
Result: 75% chance of winning! Did you answer this riddle correctly?
YES NO
White And Brittle
These are a part of your body
Sometimes theyre large, sometimes theyre little
Theyre white and they can be broken
And in some people they are brittle
What could these things be?
Sometimes theyre large, sometimes theyre little
Theyre white and they can be broken
And in some people they are brittle
What could these things be?
Hint:
You See A Boat Riddle
You see a boat filled with people. It has not sunk, but when you look again, you don't see a single person there. Why?
Hint:
You Are Driving A Bus Riddle
You are driving a bus, Six people get on, two people get off, then 10 people get on and five people get off, then eight people get on and four more people get off.
What color were the bus driver's eyes?
What color were the bus driver's eyes?
Hint:
10 Apples In A Basket Riddle
There are 10 apples in a basket. There are 10 people. Each person takes an apple but there is still one apple left in the basket. How can this be?
Hint:
Billions Of Eyes
I have billions of eyes, yet I live in darkness. I have millions of ears, yet only four lobes. I have no muscle, yet I rule two hemispheres. What am I?
Hint:
Bees On The Way To School
Hint:
Add Your Riddle Here
Have some tricky riddles of your own? Leave them below for our users to try and solve.