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
Over London Bridge
As I went over London Bridge
I met my sister Jenny
I broke her neck and drank her blood
And left her standing empty
Who is Jenny?
I met my sister Jenny
I broke her neck and drank her blood
And left her standing empty
Who is Jenny?
Hint:
Going To London Riddle
While I was going to London I met a men with 7 wives, 7 sacks, 7 kids and 7 cats. How many were going to London?
Hint:
Bus Driver Riddle
Ok, you're the bus driver, there were 20 kids on the bus. At the first stop, 2 kids get on but 5 kids get off. The second stop, 3 kids get off but 1 gets on. The third stop, 8 kids get off but only 3 kids get off. Who's the bus driver?
Hint:
What Can You Hold In Your Right Hand Riddle
Hint:
Facebook Llama Riddle Challenge
Its 3am, the doorbell rings and you wake up. Unexpected visitors!!
Its your parents and they are here for breakfast.
You have strawberry jam, honey, wine, bread and cheese.
What is the first thing you open?
Its your parents and they are here for breakfast.
You have strawberry jam, honey, wine, bread and cheese.
What is the first thing you open?
Hint:
You will Open your Eyes first, then you will Open the door. Did you answer this riddle correctly?
YES NO
YES NO
How Many Days In A Year Riddle
If a year has 365 days and a leap year has 366 days, then according to time, how many days in a year would have 24 hours?
Hint:
363 days. When daylight savings time starts, that day would consist of 23 hours of time, because the clock advances an hour and when the daylight savings time ends, that day would consist of 25 hours of time, because the clock goes back to the standard time. Did you answer this riddle correctly?
YES NO
YES NO
7 Candles Riddle
Hint:
7, we asked 'how many candles' not 'how many lit candles' Did you answer this riddle correctly?
YES NO
YES NO
A Cruise Between Mexico And The USA Riddle
A man sails off on a cruise between Mexico and the USA. He does not stop at any ports and does not even come out of the cabin, yet he makes $300,000 from his trip. How?
Hint:
7 Ice Cubes Riddle
I have 7 ice cubes inside a cup of water how many ice cubes do I have left after putting the cup in the freezer?
Hint:
The Most Amount Of Money
Hint:
Mary! John 'had' 200k but is past tense. Mark 'will' have 500k but does not current have it as the question asks who 'has' the most amount of money. Did you answer this riddle correctly?
YES NO
YES NO
A Girl Was Crying Riddle
A girl was crying because her boyfriend left her, she broke a bottle and a chair... what broke first?
Hint:
In The Jar Riddle
A jar is put on the edge of the table in such a way that half of it is left hanging. What is in the jar?
Hint:
A Girl Unlocks Her Boyfriend's Phone Riddle
A girl unlocks her boyfriend's phone. She found three different contacts having the same name "LOVE". 1st "Love" is the daughter of his dad's dad daughter in law. 2nd "Love" is the mother of his mother and 3rd one is she herself.
Hows the 1st contact is related to the 2nd one?
Hows the 1st contact is related to the 2nd one?
Hint:
The Fourth Column Riddle
The fourth column has question marks in the place of numbers.
Do you know which one of the given options will take place of the fourth column?
Do you know which one of the given options will take place of the fourth column?
Hint:
The correct choice will be the option 'd'.
In each succeeding row, the previous column is reversed and the lowest digits are omitted. Did you answer this riddle correctly?
YES NO
In each succeeding row, the previous column is reversed and the lowest digits are omitted. Did you answer this riddle correctly?
YES NO
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