The Last Cookie Riddle
Mike and James are arguing over who gets the last cookie in the jar, so their dad decides to create a game to settle their dispute. First, Mike flips a coin twice, and each time James calls heads or tails in the air. If James gets both calls right, he gets the last cookie. If not, Mike picks a number between one and six and then rolls a die. If he gets the number right, he gets the last cookie. If not, James picks two numbers between one and five, then spins a spinner with numbers one through five on it. If the spinner lands on one of James' two numbers, he gets the last cookie. If not, Mike does.
Who is more likely to win the last cookie, Mike or James? And what is the probability that person wins it?
Who is more likely to win the last cookie, Mike or James? And what is the probability that person wins it?
Hint: Their dad is a very smart person.
Believe it or not, both Mike and James have a 1/2 chance of winning.
James wins if:
-he calls both coin flips right = 1/2 x 1/2 = 1/4
OR
-he does not call both coin flips right, Mike does not call the die roll correctly, and he guesses the number on the spinner right = 3/4 x 5/6 x 2/5 = 30/120 = 1/4
1/4 + 1/4 = 1/2
Mike wins if:
-James does not call both coin flips right and he calls the die roll correctly = 3/4 x 1/6 = 3/24 = 1/8
OR
-James does not call both coin flips right, he does not call the die roll correctly, and Mike does not guess the number on the spinner right = 3/4 x 5/6 x 3/5 = 45/120 = 3/8
1/8 + 3/8 = 1/2
Of course, dad could have just flipped a coin Did you answer this riddle correctly?
YES NO
James wins if:
-he calls both coin flips right = 1/2 x 1/2 = 1/4
OR
-he does not call both coin flips right, Mike does not call the die roll correctly, and he guesses the number on the spinner right = 3/4 x 5/6 x 2/5 = 30/120 = 1/4
1/4 + 1/4 = 1/2
Mike wins if:
-James does not call both coin flips right and he calls the die roll correctly = 3/4 x 1/6 = 3/24 = 1/8
OR
-James does not call both coin flips right, he does not call the die roll correctly, and Mike does not guess the number on the spinner right = 3/4 x 5/6 x 3/5 = 45/120 = 3/8
1/8 + 3/8 = 1/2
Of course, dad could have just flipped a coin Did you answer this riddle correctly?
YES NO
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 Cheap Mp3 Player
My MP3 player is cheap 'n' nasty and has now broken: it is stuck on 'Shuffle'. In this mode it starts with whatever track you put it on, but then plays tracks in a random order. The only restriction is it never plays a song that's already been played that day.
I purchased my favourite murder mystery book in audio format, and put the first 6 chapters on my MP3 player. (Each chapter is exactly 1 track.) There's nothing else on my player at the moment. What is the probability that I will hear the 6 chapters in order as I listen today, without having to change tracks at all? (Obviously, I will ensure it plays chapter 1 first.)
The next day I empty the player before putting on the next 6 chapters. This time I also transfer a CD of mine with 11 songs on. I don't mind songs coming in between the chapters of my book, as long as the chapters are in order. What's the probability of that happening now?
I purchased my favourite murder mystery book in audio format, and put the first 6 chapters on my MP3 player. (Each chapter is exactly 1 track.) There's nothing else on my player at the moment. What is the probability that I will hear the 6 chapters in order as I listen today, without having to change tracks at all? (Obviously, I will ensure it plays chapter 1 first.)
The next day I empty the player before putting on the next 6 chapters. This time I also transfer a CD of mine with 11 songs on. I don't mind songs coming in between the chapters of my book, as long as the chapters are in order. What's the probability of that happening now?
Hint:
With only 6 tracks on the player:
The first chapter has been set to play first. The probability of the next 5 chapters playing in order is 1/5! = 1/120.
With the music on the player as well:
Seeing as I don't care about when the music plays, it doesn't change anything. The answer is still 1/120. Did you answer this riddle correctly?
YES NO
The first chapter has been set to play first. The probability of the next 5 chapters playing in order is 1/5! = 1/120.
With the music on the player as well:
Seeing as I don't care about when the music plays, it doesn't change anything. The answer is still 1/120. Did you answer this riddle correctly?
YES NO
Man With A Wooden Leg
Hint:
You cant take a picture with a wooden leg. You need a camera (or iPad or cell phone) to take a picture. Did you answer this riddle correctly?
YES NO
YES NO
Ticking In Its Weary Pace
Time is writ upon my face
My heart ticks in its weary pace.
Though wind and rain do leave their trace,
I watch them in their endless race.
What kind of clock is it, though?
My heart ticks in its weary pace.
Though wind and rain do leave their trace,
I watch them in their endless race.
What kind of clock is it, though?
Hint:
Unwilling To Kiss
First think of the person who lives in disguise,
Who deals in secrets and tells naught but lies.
Next, tell me whats always the last thing to mend,
The middle of middle and end of the end?
And finally give me the sound often heard
During the search for a hard-to-find word.
Now string them together, and answer me this,
Which creature would you be unwilling to kiss?
Who deals in secrets and tells naught but lies.
Next, tell me whats always the last thing to mend,
The middle of middle and end of the end?
And finally give me the sound often heard
During the search for a hard-to-find word.
Now string them together, and answer me this,
Which creature would you be unwilling to kiss?
Hint:
The Quietest Whimper
I talk, but I do not speak my mind
I hear words, but I do not listen to thoughts
When I wake, all see me
When I sleep, all hear me
Many heads are on my shoulders
Many hands are at my feet
The strongest steel cannot break my visage
But the softest whisper can destroy me
The quietest whimper can be heard.
What am I?
I hear words, but I do not listen to thoughts
When I wake, all see me
When I sleep, all hear me
Many heads are on my shoulders
Many hands are at my feet
The strongest steel cannot break my visage
But the softest whisper can destroy me
The quietest whimper can be heard.
What am I?
Hint:
When You Are Sad Riddle
When you are sad
You tear out my insides
When I am finished
You crush my outsides
You choose my insides
Whatever feels good
Picking out my outsides
Thinking about yourself
What am I?
You tear out my insides
When I am finished
You crush my outsides
You choose my insides
Whatever feels good
Picking out my outsides
Thinking about yourself
What am I?
Hint:
A tissue box
When you are crying, you use a tissue to wipe your tears
When all of the tissues are gone, you crush the box, and recycle it
Usually you would like a nice tissue, not a scratchy one
The outside of a tissue box can explain your personality Did you answer this riddle correctly?
YES NO
When you are crying, you use a tissue to wipe your tears
When all of the tissues are gone, you crush the box, and recycle it
Usually you would like a nice tissue, not a scratchy one
The outside of a tissue box can explain your personality Did you answer this riddle correctly?
YES NO
Baseball Caves Riddle
Hint:
Tree Embroidery Riddle
Hint:
Falling Thespians Riddle
Hint:
Kidnapping The Queens Son
The Queen lives in a beautiful castle with her only son and a sheep-dog named Sir FooFoo. One day the Queen decides to go out for a spot of tea with some friends. She leaves her eight-year-old son in the care of her trusted servants. The 18 servants are: Harold the health instructor, Griffith the gardener, Tiffany the private tutor, Philip the photographer, Magdalina the maid, Boris the Butler, Geraldo the groundskeeper, Bernadette the barber, Sandy the sweeper, Anastasia the accountant, Constantine the carpenter, Joel the jester, Lucy the launderer, Sadie the seamstress, McKenzie the musical instructor, Lawrence the lawyer, Dorothy the dentist, Devon the doctor, and Surlamina the Secretary of State. When the Queen came home she discovered her son was missing and that he was kidnapped. The Queen came to a conclusion that it must've been one of her servants who kidnapped her son because he was too young to leave on his own and Sir FooFoo was harmless. The Queen interviewed all of her servants to see which one was responsible for the kidnapping. The alibis are as follows: Harold was lifting weights, Griffith was planting roses, Tiffany was checking homework, Philip was taking pictures of the botanical garden, Magdalina was making the beds, Boris was cleaning the banisters, Geraldo was supervising Griffith , Bernadette was trimming Sir FooFoo's hair, Sandy was sweeping in the corners, Anastasia was managing the Queen's affairs, Constantine was building a birdhouse, Joel was coming up with the jokes, Lucy was doing the laundry, Sadie was designing a dress for the Queen, McKenzie was playing the flute, Lawrence was suing the bank, Dorothy was preparing to extract the Queen's tooth when the Queen came home, Devon was examining an x-ray of the Queen's arm, and Surlamina was being a Secretary of State.
Who is the kidnapper?
Who is the kidnapper?
Hint:
Surlamina is responsible for the kidnapping because there is no Secretary of State in a monarchy. It is believed that Surlamina kidnapped the Queen's son because she was not given a real job. Did you answer this riddle correctly?
YES NO
YES NO
Between An Elephant's Toes Riddle
Hint:
Associated With Cob
Im yellow but Im not the sun
I grow in a field but Im not a sunflower
Im found on an ear but Im not a piece of jewelry
I go well with butter but Im not a slice of toast
Im associated with cob but Im not a web
What am I?
I grow in a field but Im not a sunflower
Im found on an ear but Im not a piece of jewelry
I go well with butter but Im not a slice of toast
Im associated with cob but Im not a web
What am I?
Hint:
Sweet And Bakes Riddle
I have eyes but I cant see
I have skin but I cant feel anything
I can be sweet but Im not a piece of candy
I can be baked but Im not a cake
I can be peeled but Im not a carrot
What could I be?
I have skin but I cant feel anything
I can be sweet but Im not a piece of candy
I can be baked but Im not a cake
I can be peeled but Im not a carrot
What could I be?
Hint:
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