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
The Loaded Revolver Riddle
Henry has been caught stealing cattle, and is brought into town for justice. The judge is his ex-wife Gretchen, who wants to show him some sympathy, but the law clearly calls for two shots to be taken at Henry from close range. To make things a little better for Henry, Gretchen tells him she will place two bullets into a six-chambered revolver in successive order. She will spin the chamber, close it, and take one shot. If Henry is still alive, she will then either take another shot, or spin the chamber again before shooting.
Henry is a bit incredulous that his own ex-wife would carry out the punishment, and a bit sad that she was always such a rule follower. He steels himself as Gretchen loads the chambers, spins the revolver, and pulls the trigger. Whew! It was blank. Then Gretchen asks, "Do you want me to pull the trigger again, or should I spin the chamber a second time before pulling the trigger?"
What should Henry choose?
Henry is a bit incredulous that his own ex-wife would carry out the punishment, and a bit sad that she was always such a rule follower. He steels himself as Gretchen loads the chambers, spins the revolver, and pulls the trigger. Whew! It was blank. Then Gretchen asks, "Do you want me to pull the trigger again, or should I spin the chamber a second time before pulling the trigger?"
What should Henry choose?
Hint:
Henry should have Gretchen pull the trigger again without spinning.
We know that the first chamber Gretchen fired was one of the four empty chambers. Since the bullets were placed in consecutive order, one of the empty chambers is followed by a bullet, and the other three empty chambers are followed by another empty chamber. So if Henry has Gretchen pull the trigger again, the probability that a bullet will be fired is 1/4.
If Gretchen spins the chamber again, the probability that she shoots Henry would be 2/6, or 1/3, since there are two possible bullets that would be in firing position out of the six possible chambers that would be in position. Did you answer this riddle correctly?
YES NO
We know that the first chamber Gretchen fired was one of the four empty chambers. Since the bullets were placed in consecutive order, one of the empty chambers is followed by a bullet, and the other three empty chambers are followed by another empty chamber. So if Henry has Gretchen pull the trigger again, the probability that a bullet will be fired is 1/4.
If Gretchen spins the chamber again, the probability that she shoots Henry would be 2/6, or 1/3, since there are two possible bullets that would be in firing position out of the six possible chambers that would be in position. Did you answer this riddle correctly?
YES NO
Knights Of The Round Table Riddle
King Arthur, Merlin, Sir Lancelot, Sir Gawain, and Guinevere decide to go to their favorite restaurant to share some mead and grilled meats. They sit down at a round table for five, and as soon as they do, Lancelot notes, "We sat down around the table in age order! What are the odds of that?"
Merlin smiles broadly. "This is easily solved without any magic." He then shared the answer. What did he say the odds were?
Merlin smiles broadly. "This is easily solved without any magic." He then shared the answer. What did he say the odds were?
Hint: Does it matter if they are sitting clockwise or counterclockwise? Or where the oldest sits?
The odds are 11:1. (The probability is 1/12.)
Imagine they sat down in age order, with each person randomly picking a seat. The first person is guaranteed to pick a seat that "works". The second oldest can sit to his right or left, since these five can sit either clockwise or counterclockwise. The probability of picking a seat that works is thus 2/4, or 1/2. The third oldest now has three chairs to choose from, one of which continues the progression in the order determined by the second person, for a probability of 1/3. This leaves two seats for the fourth oldest, or a 1/2 chance. The youngest would thus be guaranteed to sit in the right seat, since there is only one seat left. This gives 1 * 1/2 * 1/3 * 1/2 * 1 = 1/12, or 11:1 odds against. Did you answer this riddle correctly?
YES NO
Imagine they sat down in age order, with each person randomly picking a seat. The first person is guaranteed to pick a seat that "works". The second oldest can sit to his right or left, since these five can sit either clockwise or counterclockwise. The probability of picking a seat that works is thus 2/4, or 1/2. The third oldest now has three chairs to choose from, one of which continues the progression in the order determined by the second person, for a probability of 1/3. This leaves two seats for the fourth oldest, or a 1/2 chance. The youngest would thus be guaranteed to sit in the right seat, since there is only one seat left. This gives 1 * 1/2 * 1/3 * 1/2 * 1 = 1/12, or 11:1 odds against. Did you answer this riddle correctly?
YES NO
Safe And Secure Riddle
As a whole, I am both safe and secure.
Behead me, and I become a place of meeting.
Behead me again, and I am the partner of ready.
Restore me, and I become the domain of beasts.
What am I?
Behead me, and I become a place of meeting.
Behead me again, and I am the partner of ready.
Restore me, and I become the domain of beasts.
What am I?
Hint:
Born In London Riddle
Simon Simpleton was born in London, England.
His mother was Welsh and his father Scottish.
When Simon was eight his mother died.
When Simon was ten his father married an Irish women and suddenly Simon had an Irish sister.
When Simon was twenty four he graduated as a lawyer and took a job in Edinburgh, Scotland.
He is now sixty six.
Why can he not be buried on the banks of Loch Lomond in his favorite village of Luss, in Bonnie Scotland?
His mother was Welsh and his father Scottish.
When Simon was eight his mother died.
When Simon was ten his father married an Irish women and suddenly Simon had an Irish sister.
When Simon was twenty four he graduated as a lawyer and took a job in Edinburgh, Scotland.
He is now sixty six.
Why can he not be buried on the banks of Loch Lomond in his favorite village of Luss, in Bonnie Scotland?
Hint:
Taking You To School
This vehicle makes frequent stops
So getting to places can be slow
In London theyre usually red
The ones you take to school are yellow
So getting to places can be slow
In London theyre usually red
The ones you take to school are yellow
Hint:
Trombone Playground Equipment Riddle
Hint:
Mathtastic Desserts
Hint:
Lights On A String
People go round and round me
Adding some lights on a string
And later underneath me
They place the gifts that they bring.
I am a...
Adding some lights on a string
And later underneath me
They place the gifts that they bring.
I am a...
Hint:
The Fourth Column Riddle
The fourth column has question marks in the place of numbers.
Do you know which one of the given options will take place of the fourth column?
Do you know which one of the given options will take place of the fourth column?
Hint:
The correct choice will be the option 'd'.
In each succeeding row, the previous column is reversed and the lowest digits are omitted. Did you answer this riddle correctly?
YES NO
In each succeeding row, the previous column is reversed and the lowest digits are omitted. Did you answer this riddle correctly?
YES NO
Riddle Of The Two Barbers
A man arrives at a small town and needs to get his hair cut. He discovers there are just two barbers in the town. He visits the first one and finds that he has a clean haircut and a clean place. Then he visits the second one and finds his place is a mess and he has an awful haircut.
After a moment of consideration, he decides to have his haircut done by the second barber.
Why?
After a moment of consideration, he decides to have his haircut done by the second barber.
Why?
Hint:
Both barbers must go to the other barber to get their haircuts. Since the first barber had a clean haircut, that means the second barber gives good haircuts and the first barber doesn't. Did you answer this riddle correctly?
YES NO
YES NO
Throw Me Off The Highest Building Riddle
I won't break if you throw me off from the highest building but I will break if you place me in the ocean. What am I?
Hint:
Open Lock Riddle - Can You Open The Lock?
In this puzzle, a number lock has 3 digit key and you will have to find out the correct combination to open the lock. Can you solve this number lock puzzle 682?
6, 8, 2 - One number is correct and well placed.
6, 4, 5 - One number is correct but wrong place.
2, 0, 6 - Two numbers are correct but wrong places.
7, 3, 8 - Nothing is correct.
7, 8, 0 - One number is correct but wrong place.
6, 8, 2 - One number is correct and well placed.
6, 4, 5 - One number is correct but wrong place.
2, 0, 6 - Two numbers are correct but wrong places.
7, 3, 8 - Nothing is correct.
7, 8, 0 - One number is correct but wrong place.
Hint:
Crispy Pie Riddles
I'm a dessert that's fruity and sweet,
With a crispy crust that's hard to beat.
I'm often served in the summertime,
And I'm a favorite of many who dine.
What am I?
With a crispy crust that's hard to beat.
I'm often served in the summertime,
And I'm a favorite of many who dine.
What am I?
Hint: This pie is often made with a variety of berries, and can be served warm or cold.
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