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
Fox Goose Beans Riddle
Hint:
The first step must be to take the goose across the river, as any other will result in the goose or the beans being eaten. When the farmer returns to the original side, he has the choice of taking either the fox or the beans across next. If he takes the fox across, he would have to return to get the beans, resulting in the fox eating the goose. If he takes the beans across second, he will need to return to get the fox, resulting in the beans being eaten by the goose. The dilemma is solved by taking the fox (or the beans) over and bringing the goose back. Now he can take the beans (or the fox) over, and finally return to fetch the goose. His actions in the solution are summarized in the following steps: Take the Goose over Return Take the beans over Return with the goose Take the fox over Return Take goose over Thus there are seven crossings, four forward and three back. Did you answer this riddle correctly?
YES NO
YES NO
Lambs Goats Turkeys Scottish Field Riddle
You're standing in a Scottish field with green as far as the eye can see and you're standing alone. You check left, you check right and there's nobody anywhere. Out of the horizon the farthest distance away, comes three lambs. They come up to you and say hello. The first one says "My names Marley!", the second one says "My names Barley!", and the third one says "My names Richard!"
You say hello to each and then they go "baaah" and go right back to where they came from. On your left you see three goats approach you from the horizon. "Hello! My names Billy!", My names Jilly!", "My names Willie!" You say hello to each and then they go "baaah" and go back to where they came. On your right you see three turkeys approach you from the horizon. "Hello! My names Veronica!", "My names Maisel!", "My names Brittney!"
You reply hello to each and then they go "baaah" and go back to where they came. All is silent and then you start thinking whos gonna come up behind me? So you turn around.
What three animals approach from behind you and what are their names?
You say hello to each and then they go "baaah" and go right back to where they came from. On your left you see three goats approach you from the horizon. "Hello! My names Billy!", My names Jilly!", "My names Willie!" You say hello to each and then they go "baaah" and go back to where they came. On your right you see three turkeys approach you from the horizon. "Hello! My names Veronica!", "My names Maisel!", "My names Brittney!"
You reply hello to each and then they go "baaah" and go back to where they came. All is silent and then you start thinking whos gonna come up behind me? So you turn around.
What three animals approach from behind you and what are their names?
Hint:
I Had 3.00 Riddle
Hint:
The correct answer is 8 dollars. If you read the question carefully, the question asked about your first money with "how much money Did I really have?"
The money you had is 10 dollars. That is before your parents and relatives gave you additional money.
However, given that the logic and time of the tense is in the past, it is safe to assume that the question pertains to the money you had originally before you received external money from someone else. Did you answer this riddle correctly?
YES NO
The money you had is 10 dollars. That is before your parents and relatives gave you additional money.
However, given that the logic and time of the tense is in the past, it is safe to assume that the question pertains to the money you had originally before you received external money from someone else. Did you answer this riddle correctly?
YES NO
10 Fish In A Tank Riddle
Hint: They're inside a tank
Who Is Asleep On Your Couch
Hint: It's not her brother-in-law
What Kind Of Room Has No Doors Or Windows Riddle
Hint:
What Seven Letter Word
Hint: This word is heavy.
Up The Chimney
Hint: You'll need this is it rains.
Four Daughters
Hint:
Building With Silver And Gold
Hint:
Three Feet
Hint:
Keeping The Time
Hint:
Cats And Colors
Hint:
Carrying Trees
Hint:
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