The Gardners Riddle
Gretchen and Henry were discussing their new neighbors, the Gardners. Gretchen mentioned that she met two of the daughters, and they each had blond hair.
"I have met all of the sisters," replied Henry, "and the probability that both of the girls you met would have had blond hair, assuming you were equally likely to meet any of the sisters, is exactly 50%. Do you know how many children there are?"
After thinking for a minute, Gretchen asks if the family is abnormally large. When Henry replies that it is not, Gretchen tells him how many girls are in the family. What number did she say?
"I have met all of the sisters," replied Henry, "and the probability that both of the girls you met would have had blond hair, assuming you were equally likely to meet any of the sisters, is exactly 50%. Do you know how many children there are?"
After thinking for a minute, Gretchen asks if the family is abnormally large. When Henry replies that it is not, Gretchen tells him how many girls are in the family. What number did she say?
Hint:
Gretchen said that there were 4 girls in the family, three of whom were blond.
This would make the probability that she saw two blonds (3/4) * (2/3), which equals 1/2.
Other numbers would work, but the next pair would lead to a rather large family. Did you answer this riddle correctly?
YES NO
This would make the probability that she saw two blonds (3/4) * (2/3), which equals 1/2.
Other numbers would work, but the next pair would lead to a rather large family. Did you answer this riddle correctly?
YES NO
Under The Cup Riddle
You decide to play a game with your friend where your friend places a coin under one of three cups. Your friend would then switch the positions of two of the cups several times so that the coin under one of the cups moves with the cup it is under. You would then select the cup that you think the coin is under. If you won, you would receive the coin, but if you lost, you would have to pay.
As the game starts, you realise that you are really tired, and you don't focus very well on the moving of the cups. When your friend stops moving the cups and asks you where the coin is, you only remember a few things:
He put the coin in the rightmost cup at the start.
He switched two of the cups 3 times.
The first time he switched two of the cups, the rightmost one was switched with another.
The second time he switched two of the cups, the rightmost one was not touched.
The third and last time he switched two of the cups, the rightmost one was switched with another.
You don't want to end up paying your friend, so, using your head, you try to work out which cup is most likely to hold the coin, using the information you remember.
Which cup is most likely to hold the coin?
As the game starts, you realise that you are really tired, and you don't focus very well on the moving of the cups. When your friend stops moving the cups and asks you where the coin is, you only remember a few things:
He put the coin in the rightmost cup at the start.
He switched two of the cups 3 times.
The first time he switched two of the cups, the rightmost one was switched with another.
The second time he switched two of the cups, the rightmost one was not touched.
The third and last time he switched two of the cups, the rightmost one was switched with another.
You don't want to end up paying your friend, so, using your head, you try to work out which cup is most likely to hold the coin, using the information you remember.
Which cup is most likely to hold the coin?
Hint: Write down the possibilities. Remember that there are only three cups, so if the rightmost cup wasn't touched...
The rightmost cup.
The rightmost cup has a half chance of holding the coin, and the other cups have a quarter chance.
Pretend that Os represent cups, and Q represents the cup with the coin.
The game starts like this:
OOQ
Then your friend switches the rightmost cup with another, giving two possibilities, with equal chance:
OQO
QOO
Your friend then moves the cups again, but doesn't touch the rightmost cup. The only switch possible is with the leftmost cup and the middle cup. This gives two possibilities with equal chance:
QOO
OQO
Lastly, your friend switches the rightmost cup with another cup. If the first possibility shown above was true, there would be two possibilities, with equal chance:
OOQ
QOO
If the second possibility shown above (In the second switch) was true, there would be two possibilities with equal chance:
OOQ
OQO
This means there are four possibilities altogether, with equal chance:
OOQ
QOO
OOQ
OQO
This means each possibility equals to a quarter chance, and because there are two possibilities with the rightmost cup having the coin, there is a half chance that the coin is there. Did you answer this riddle correctly?
YES NO
The rightmost cup has a half chance of holding the coin, and the other cups have a quarter chance.
Pretend that Os represent cups, and Q represents the cup with the coin.
The game starts like this:
OOQ
Then your friend switches the rightmost cup with another, giving two possibilities, with equal chance:
OQO
QOO
Your friend then moves the cups again, but doesn't touch the rightmost cup. The only switch possible is with the leftmost cup and the middle cup. This gives two possibilities with equal chance:
QOO
OQO
Lastly, your friend switches the rightmost cup with another cup. If the first possibility shown above was true, there would be two possibilities, with equal chance:
OOQ
QOO
If the second possibility shown above (In the second switch) was true, there would be two possibilities with equal chance:
OOQ
OQO
This means there are four possibilities altogether, with equal chance:
OOQ
QOO
OOQ
OQO
This means each possibility equals to a quarter chance, and because there are two possibilities with the rightmost cup having the coin, there is a half chance that the coin is there. Did you answer this riddle correctly?
YES NO
Snowman Playing Piano Riddle
Hint:
Quite Grand
Hint:
A Character In Thomas And Friends
Shes a character in Thomas And Friends
But her names not Emily I should stress
She also has the name of a flower
And in Mario games shes a Princess
What could I be?
But her names not Emily I should stress
She also has the name of a flower
And in Mario games shes a Princess
What could I be?
Hint:
Hundreds Of These In A Graveyard
There are hundreds of these in a graveyard
But dead bodies it is not
Its what contains all the info as to
Whos in each burial plot
What is it?
But dead bodies it is not
Its what contains all the info as to
Whos in each burial plot
What is it?
Hint:
People Cry At My Sight
I have a name that's not mine,
and no one cares about me in their prime.
People cry at my sight,
and lie by me all day and night.
What am I?
and no one cares about me in their prime.
People cry at my sight,
and lie by me all day and night.
What am I?
Hint:
Two Camels Riddle
Two camels were facing in opposite directions. One was facing due East and one was facing due West. They were in the desert so there was no reflection. How can they manage to see each other without walking around or turning around or moving their heads?
Hint:
The two camels were facing each other the entire time. Hence facing in opposite directions. Did you answer this riddle correctly?
YES NO
YES NO
Brown With No Legs
Hint:
Shaped Like A Box
Hint:
The Tenth Floor Elevator Riddle
A man lives on the tenth floor of a building. Every day he takes the elevator to go down to the ground floor to go to work. When he returns he takes the same elevator to the seventh floor and walks up the stairs to reach his apartment on the tenth floor. He hates walking so why does he do it?
Note that there is nothing wrong with the elevator or the design of the building. It's a perfectly normal elevator in a perfectly normal building.
Note that there is nothing wrong with the elevator or the design of the building. It's a perfectly normal elevator in a perfectly normal building.
Hint: The elevator is perfectly normal and the design of the building is perfectly normal, but there is something different about the man.
The man is very short (i.e. a little person).
Because of his short stature, the man is unable to reach any higher than the button for the 7th floor (elevator floor number buttons are laid out in descending floor order from top to bottom). Did you answer this riddle correctly?
YES NO
Because of his short stature, the man is unable to reach any higher than the button for the 7th floor (elevator floor number buttons are laid out in descending floor order from top to bottom). Did you answer this riddle correctly?
YES NO
Speaking With A Hard Tongue
Hint:
Sitting On A Pirates Shoulder
This is a certain type of bird
But it is not a hawk
It sits on a pirate's shoulder
While letting out a squawk
But it is not a hawk
It sits on a pirate's shoulder
While letting out a squawk
Hint:
Lips That Can Kiss
Its red and part of your body
But it is not lips that can kiss
Instead its a type of liquid
Mosquitos like to suck up this
it is?
But it is not lips that can kiss
Instead its a type of liquid
Mosquitos like to suck up this
it is?
Hint:
Throwing A Basketball Riddle
A man takes a basketball and throws it as hard as he can. There is nothing in front, behind, or on either side of him, and yet, the ball comes back and hits him square in the face. How can this be?
Hint:
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