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
Throw The Clock Out The Window Riddle
Hint:
Phoning A Clown Riddle
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What Does A Rain Cloud Wear Riddle
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Sad Clown Riddle
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Clown Outfit Riddle
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Clown And A Goat Riddle
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A 7 Foot Clown Riddle
A 7 foot clown stood up and held a water glass over his head. He accidentally dropped the glass, but nothing spilled. How is this possible?
Hint:
12 Clowns Riddle
On my way to the fair, I met a group. The group consisted of 12 clowns. Each clown had 30 cats, each cat had 20 hats, each hat had 41 rats, each rat had 4 mice, and each mice had 79 lice. How many of us were going to the fair?
Hint:
Mermaid Math Class Riddle
Hint:
A Grandfather Clock Riddle
A grandfather clock chimes the appropriate number of times to indicate the hour, as well as chiming once at each quarter hour. If you were in another room and heard the clock chime just once, what would be the longest period of time you would have to wait in order to be certain of the correct time? Assuming you had absolutely no clue what time it was.
Hint:
You would have to wait 90 minutes between 12:15 and 1:45. Once you had heard seven single chimes, you would know that the next chime would be two chimes for 2 oclock.
In order for daylight savings time to come into play, you would have to manually set the clock back, which unless you did it with your eyes closed would indicate the time to you. Did you answer this riddle correctly?
YES NO
In order for daylight savings time to come into play, you would have to manually set the clock back, which unless you did it with your eyes closed would indicate the time to you. Did you answer this riddle correctly?
YES NO
Cookie Banana Clock Riddle
Hint:
Look closely and notice 2 things in above picture:
No. of chocolate pieces on each cookie
Time in clock
Cookie(10 chocs) + Cookie(10 chocs) + Cookie(10 chocs) = 30 ==> Cookie with 10 chocs = 10
2 bananas + 2 bananas + Cookie(10 chocs) = 14
4 Bananas + 10 =14 ==> Banana = 1
2 Bananas + Clock(3 O'clock) + Clock(3 O'clock) = 8 Did you answer this riddle correctly?
YES NO
No. of chocolate pieces on each cookie
Time in clock
Cookie(10 chocs) + Cookie(10 chocs) + Cookie(10 chocs) = 30 ==> Cookie with 10 chocs = 10
2 bananas + 2 bananas + Cookie(10 chocs) = 14
4 Bananas + 10 =14 ==> Banana = 1
2 Bananas + Clock(3 O'clock) + Clock(3 O'clock) = 8 Did you answer this riddle correctly?
YES NO
Pirate Class Riddle
Hint:
Santa And A Space Ship
Hint:
Deep Fried Santa Riddle
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