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:
What Can You Hold In Your Right Hand Riddle
Hint:
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 Train Leaves From Halifax Riddle
Hint:
Both trains would be at the same spot when they meet therefore they are both equally close to Halifax. Did you answer this riddle correctly?
YES NO
YES NO
Parents Over For Breakfast
Hint:
7 Ice Cubes Riddle
Hint:
A Girl Was Crying Riddle
Hint:
In The Jar Riddle
Hint:
I Am A 8 Letter Word Riddle
I am kept Secret from Everyone.
My 2nd, 3rd, 4th Letter Spell an Animal.
My 4th, 5th, 6th, 7th, 8th Letter is a Weapon.
My 1st, 2nd, 8th Letter is used for Writing an Exam.
My 3rd, 4th Letters are the Same.
Who am I?
Hint:
Borrow $50 From Mom And $50 From Dad Riddle
Hint:
Total Money taken = $100($50+$50)
Now,
Bag's Price = $ 97
Remaining Amount = $100 - $97
= $ 3
Returned = $ 1 + $ 1
=$2
In pocket = $1
Total money owed = $100- ( Returned amount)
= $98( Bag's amount and reserved amount)
So, it was a calculation mistake. Did you answer this riddle correctly?
YES NO
Now,
Bag's Price = $ 97
Remaining Amount = $100 - $97
= $ 3
Returned = $ 1 + $ 1
=$2
In pocket = $1
Total money owed = $100- ( Returned amount)
= $98( Bag's amount and reserved amount)
So, it was a calculation mistake. Did you answer this riddle correctly?
YES NO
17 Cows Riddle
One day, their neighbor came by to see how they were doing after their father's death. The three sons told him their problem. After thinking for a while, the neighbor said: "I'll be right back!" He went away, and when he came back, the three sons could divide the cows according to their father's will, and in such a way that each of them got a whole number of cows.
What was the neighbor's solution?
Hint:
The neighbour borrowed an extra cow, to make the total number of cows 18. Then the oldest son got 1/2 of 18 is 9 cows, the middle son got 1/3 of 18 is 6 cows, and the youngest son got 1/9 of 18 is 2 cows. Since 9+6+2 = 17, the cows could be divided among the three brothers in such a way that the borrowed cow was left over, and could be returned to its owner. Did you answer this riddle correctly?
YES NO
YES NO
Billy left for college in 2019.
Harry left in 2020.
Mark left in 2023.
Who left first?
Hint:
The mother. In order for Mark to be a single dad, the mother had to leave him and the kids first. Did you answer this riddle correctly?
YES NO
YES NO
A Man Comes Home From Work Riddle
He immediately runs out and calls the police, informing him that his wife is in danger? Why?
Hint:
The Man was Blind so he suspects that his wife is in some danger and thus calls the police. Did you answer this riddle correctly?
YES NO
YES NO
26 Sheep In A Field In A Field Riddle
Hint:
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