The Secret Santa Exchange
A group of ten friends decide to exchange gifts as secret Santas. Each person writes his or her name on a piece of paper and puts it in a hat. Then each person randomly draws a name from the hat to determine who has him as his or her secret Santa. The secret Santa then makes a gift for the person whose name he drew.
When it's time to exchange presents, each person walks over to the person he made the gift for and holds his or her left hand in his right hand.
What is the probability that the 10 friends holding hands form a single continuous circle?
When it's time to exchange presents, each person walks over to the person he made the gift for and holds his or her left hand in his right hand.
What is the probability that the 10 friends holding hands form a single continuous circle?
Hint: It's not as difficult as it seems.
It's the number of ways the friends can form a circle divided by the number of ways the names can be drawn out of the hat.
1/10
For a group of n friends, there are n! (n factorial) ways to draw the names out of the hat. Since a circle does not have a beginning and end, choose one person as the beginning and end of the circle. There are now (n-1)! ways to distribute the remaining people around the circle. Thus the probability of forming a single circle is
(n-1)! / n!
Since n! = (n-1)! * n (for n > 1), this can be rewritten as
(n-1)! / (n*(n-1)!)
Factoring out the (n-1)! from the numerator and denominator leaves
1/n
as the probability. Did you answer this riddle correctly?
YES NO
For a group of n friends, there are n! (n factorial) ways to draw the names out of the hat. Since a circle does not have a beginning and end, choose one person as the beginning and end of the circle. There are now (n-1)! ways to distribute the remaining people around the circle. Thus the probability of forming a single circle is
(n-1)! / n!
Since n! = (n-1)! * n (for n > 1), this can be rewritten as
(n-1)! / (n*(n-1)!)
Factoring out the (n-1)! from the numerator and denominator leaves
1/n
as the probability. Did you answer this riddle correctly?
YES NO
The End Of Your Arm Riddle
This might be made into a fist
If you are not feeling calm
This is a part of your body
Thats at the end of your arm
What is it?
If you are not feeling calm
This is a part of your body
Thats at the end of your arm
What is it?
Hint:
Fish Wish Riddle
Hint:
Invisible At Night Riddle
I fly like a bird of many colors through the sky. I am made with both wood and fire but I do not burn up. You can see me clearly during the day, but I am nearly invisible at night. What am I?
Hint:
Hot Air Balloon Over The Sahara
One sunny afternoon, three men go for a ride on a hot air balloon over the Sahara desert. An hour into the trip, the balloon begins to lose altitude. A month later, someone found one of the ballooners laying on the desert sand dead, naked, and holding half a toothpick. What happened to him?
Hint:
As the balloon lost altitude, the men took of their clothes and threw them overboard to decrease the weight of the balloon. The balloon continued to drop so the men drew straws to see who would be forced to jump. The dead man in the desert drew the shortest one (the half toothpick). Did you answer this riddle correctly?
YES NO
YES NO
Elf Transportation Riddle
Hint:
Perfect For Cutting And Grinding
Hint:
Vegetable Necklace
Hint:
Three People At A Bus Stop Riddle
You're driving down the road in your car on a wild and stormy night. The weather is like a hurricane, with heavy rains, high winds, and lightning flashing constantly. While driving, you come across a partially-covered bus stop, and you can see three people waiting for a bus:
1. An old woman who looks as if she is about to die.
2. An old friend who once saved your life.
3.The perfect partner you have been dreaming about (your soulmate).
Knowing that you only have room for one passenger in your car (its a really small car), which one would you choose to offer a ride to? And why?
1. An old woman who looks as if she is about to die.
2. An old friend who once saved your life.
3.The perfect partner you have been dreaming about (your soulmate).
Knowing that you only have room for one passenger in your car (its a really small car), which one would you choose to offer a ride to? And why?
Hint:
I would give the car keys to my old friend, and let him take the old woman to the hospital. Then I would stay behind and wait for the bus with the partner of my dreams. Did you answer this riddle correctly?
YES NO
YES NO
Backwards Cheese Riddle
Hint:
A Woman Is Sitting In Her Hotel Room Riddle
A woman is sitting in her hotel room when there is a knock at the door. She opened the door to see a man whom she had never seen before. He said "oh I'm sorry, I have made a mistake, I thought this was my room." He then went down the corridor and in the elevator. The woman went back into her room and phoned security. What made the woman so suspicious of the man?
Hint:
3 Gallon Jug And 5 Gallon Jug
You have a 3-gallon and a 5-gallon jug that you can fill from a fountain of water.
The problem is to fill one of the jugs with exactly 4 gallons of water. How do you do it?
You've got to defuse a bomb by placing exactly 4 gallons (15 L) of water on a sensor. The problem is, you only have a 5 gallon (18.9 L) jug and a 3 gallons (11 L) jug on hand! This classic riddle, made famous in Die Hard 3.
The problem is to fill one of the jugs with exactly 4 gallons of water. How do you do it?
You've got to defuse a bomb by placing exactly 4 gallons (15 L) of water on a sensor. The problem is, you only have a 5 gallon (18.9 L) jug and a 3 gallons (11 L) jug on hand! This classic riddle, made famous in Die Hard 3.
Hint:
Fill the 5-jug up completely. There will be, of course, 5 gallons in the 5-jug. You must fill all the gallons up to the top, otherwise you don't actually know how much you have.
Use the water from the 5-jug to fill up the 3-jug. You're left with 3 gallons in the 3-jug and 2 gallons in the 5-jug.
Pour out the 3-gallon jug. You're left with nothing in the 3-jug and 2 gallons in the 5-jug.
Transfer the water from the 5-jug to the three jug. You're left with 2 gallons in the 3-jug. And nothing in the 5-jug.
Fill up the 5-jug completely. You now have 2 gallons in the 3-jug and 5 in the 5-jug. This means that there is 1 gallon (3.8 L) of space left in the 3-jug.
Use the water from the 5-jug to fill up the 3-jug. Fill up the last gallon of space in the 3-jug with the water from the 5-jug. This leaves you with 3 gallons in the 3-jug, and 4 gallons in the 5-jug.
Fill the 3-jug completely with water. You now have 3 gallons (11.4 L) of water.
Transfer this water into the 5-jug. You now have nothing in the 3-jug, and 3 gallons (11.4 L) in the 5-jug.
Re-fill the 3-jug with water. You now have 3 gallons (11.4 L) in the 3-jug and 3 gallons in the 5-jug.
Fill the 5-jug with water from your 3-jug. You now have 1 gallon (3.8 L) in the 3-jug and 5 gallons (18.9 L) in the 5-jug. This is because, in the last step, you only had 2 gallons (7.6 L) of space left over, so you could only pour 2 gallons.
Pour out the 5-jug and refill it with your 1 gallon. You now have nothing in the 3-jug and 1 gallon in the 5-jug
Fill up the 3-jug. You now have 3 gallons (11.4 L) in the 3-jug and 1 in the 5-jug.
Transfer the 3 gallons (11.4 L) of water into the 5-jug to end up with 4 gallons (15.1 L). Simply pour over your three gallons into the 5-jug, which only had 1 gallon (3.8 L) in it previously. 1+3=4, and a successfully defused bomb. Did you answer this riddle correctly?
YES NO
Use the water from the 5-jug to fill up the 3-jug. You're left with 3 gallons in the 3-jug and 2 gallons in the 5-jug.
Pour out the 3-gallon jug. You're left with nothing in the 3-jug and 2 gallons in the 5-jug.
Transfer the water from the 5-jug to the three jug. You're left with 2 gallons in the 3-jug. And nothing in the 5-jug.
Fill up the 5-jug completely. You now have 2 gallons in the 3-jug and 5 in the 5-jug. This means that there is 1 gallon (3.8 L) of space left in the 3-jug.
Use the water from the 5-jug to fill up the 3-jug. Fill up the last gallon of space in the 3-jug with the water from the 5-jug. This leaves you with 3 gallons in the 3-jug, and 4 gallons in the 5-jug.
Fill the 3-jug completely with water. You now have 3 gallons (11.4 L) of water.
Transfer this water into the 5-jug. You now have nothing in the 3-jug, and 3 gallons (11.4 L) in the 5-jug.
Re-fill the 3-jug with water. You now have 3 gallons (11.4 L) in the 3-jug and 3 gallons in the 5-jug.
Fill the 5-jug with water from your 3-jug. You now have 1 gallon (3.8 L) in the 3-jug and 5 gallons (18.9 L) in the 5-jug. This is because, in the last step, you only had 2 gallons (7.6 L) of space left over, so you could only pour 2 gallons.
Pour out the 5-jug and refill it with your 1 gallon. You now have nothing in the 3-jug and 1 gallon in the 5-jug
Fill up the 3-jug. You now have 3 gallons (11.4 L) in the 3-jug and 1 in the 5-jug.
Transfer the 3 gallons (11.4 L) of water into the 5-jug to end up with 4 gallons (15.1 L). Simply pour over your three gallons into the 5-jug, which only had 1 gallon (3.8 L) in it previously. 1+3=4, and a successfully defused bomb. Did you answer this riddle correctly?
YES NO
I Go Up And I Go Down Towards The Sky And The Ground Riddle
I go up and I go down,
towards the sky and the ground.
I'm present and past tense too,
Let's go for a ride, me and you.
What am I?
towards the sky and the ground.
I'm present and past tense too,
Let's go for a ride, me and you.
What am I?
Hint:
8 College Students Riddle
There was a group of 8 college students who all belonged to the mountain climbing club. One day, during the Winter, they decided to climb the tallest mountain in the area. During the ascent, the weather took a turn for the worse. They ran into trouble and were stranded near the top for two weeks.
Eventually, a rescue team managed to reach them. There were only 7 survivors. They were airlifted to a nearby hospital. After a few days, 6 of them made a full recovery, but the seventh survivor was so traumatized by the experience that he lost his mind and was put in a mental hospital.
The police questioned the remaining 6 about what happened during the two weeks they were stranded on the mountain. They asked what happened to the missing climber.
He just wandered off and never came back, they said. The police questioned each of the 6 survivors and they all told the same story.
Then, they went to the mental hospital to question the 7th survivor, but they couldnt get any sense out of him. When they asked him what happened to the missing climber, he just kept banging his head against the padded walls and repeating over and over, 8.. 8 8...
What does this mean?
Eventually, a rescue team managed to reach them. There were only 7 survivors. They were airlifted to a nearby hospital. After a few days, 6 of them made a full recovery, but the seventh survivor was so traumatized by the experience that he lost his mind and was put in a mental hospital.
The police questioned the remaining 6 about what happened during the two weeks they were stranded on the mountain. They asked what happened to the missing climber.
He just wandered off and never came back, they said. The police questioned each of the 6 survivors and they all told the same story.
Then, they went to the mental hospital to question the 7th survivor, but they couldnt get any sense out of him. When they asked him what happened to the missing climber, he just kept banging his head against the padded walls and repeating over and over, 8.. 8 8...
What does this mean?
Hint:
I Cannot Be Other Than What I Am Riddle
I cannot be other than what I am,
Until the man who made me dies,
Power and glory will fall to me finally,
Only when he last closes his eyes.
What am i?
Until the man who made me dies,
Power and glory will fall to me finally,
Only when he last closes his eyes.
What am i?
Hint:
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