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
Standing My Test
I'm seen to fly, described as hard. I can be your currency and heal all wounds, but not many things can stand my test. I am...
Hint:
Helping You Walk Riddle
Your body has two of these
But they cannot give a kiss
You use them to help you walk
And twelve inches make up this
What is this?
But they cannot give a kiss
You use them to help you walk
And twelve inches make up this
What is this?
Hint:
6 Things 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
How Many Days In A Year Riddle
Hint:
363 days. When daylight savings time starts, that day would consist of 23 hours of time, because the clock advances an hour and when the daylight savings time ends, that day would consist of 25 hours of time, because the clock goes back to the standard time. Did you answer this riddle correctly?
YES NO
YES NO
A Man Gave One Son 10 Cents Riddle
Hint:
1:45. The man gave away a total of 25 cents. He divided it between two people. Therefore, he gave a quarter to two. Did you answer this riddle correctly?
YES NO
YES NO
My Age No Longer Sits On A Calendar Riddle
Hint:
Always Coming But Never Arrives
Hint: A mythical land where 99% of all human productivity, motivation and achievement is stored.
The Red Hat
Once upon a time there lived a king who wished to find the wisest man in the realm to be his assistant. He summons the 3 known wisest men to his court and he administers the following test.
He sits them in a circle, facing each other and he says Im going to put either a red hat or a white hat on each of your heads. He proceeds to place a red hat on each of their heads. Obviously they can see each other but there are no mirrors in the room so they cant see whats on their heads. He says If you can see a red hat, raise your hand. They all raise their hands. Then he says If you can tell what color hat you have on, stand up.
Time goes on, one guy looks at another guy, he looks at the other guy. The other guy looks at him. Finally one guy stands up. The question is how did he know he was wearing a red hat?
He sits them in a circle, facing each other and he says Im going to put either a red hat or a white hat on each of your heads. He proceeds to place a red hat on each of their heads. Obviously they can see each other but there are no mirrors in the room so they cant see whats on their heads. He says If you can see a red hat, raise your hand. They all raise their hands. Then he says If you can tell what color hat you have on, stand up.
Time goes on, one guy looks at another guy, he looks at the other guy. The other guy looks at him. Finally one guy stands up. The question is how did he know he was wearing a red hat?
Hint: For a moment or two, nobody moved. Nobody knew for certain what color his hat was, and thats what told the wisest guy that all of the hats were red.
Step 1:
Wiseguy #1 knows he can see two red hats.
Step 2:
Wiseguy #1 thinks, "Hey, if I were wearing a white hat, Wiseguy #2 would see one red hat and one white."
Step 3:
Wiseguy #1 then thinks, "If I were wearing a white hat, and Wiseguy #2 saw one red hat and one white (and if he were wearing a white hat himself), then Wiseguy #3 would have seen two white hats. So, Wiseguy #3 wouldnt have raised his hand to the first question.
Wiseguy #1 thinks, "If that were true, Wiseguy #2 would be sure that he had a red hat. But since Wiseguy #2 was actually unsure about his hat color, it can only mean one thing, my hat is red." Did you answer this riddle correctly?
YES NO
Wiseguy #1 knows he can see two red hats.
Step 2:
Wiseguy #1 thinks, "Hey, if I were wearing a white hat, Wiseguy #2 would see one red hat and one white."
Step 3:
Wiseguy #1 then thinks, "If I were wearing a white hat, and Wiseguy #2 saw one red hat and one white (and if he were wearing a white hat himself), then Wiseguy #3 would have seen two white hats. So, Wiseguy #3 wouldnt have raised his hand to the first question.
Wiseguy #1 thinks, "If that were true, Wiseguy #2 would be sure that he had a red hat. But since Wiseguy #2 was actually unsure about his hat color, it can only mean one thing, my hat is red." Did you answer this riddle correctly?
YES NO
Old Man Ankit
An old man ankit lives alone in a flat. Because of his age , he is not able to move comfortably and hence most of the things used to be delivered to his house.
On Friday while delivering the mail , postman feels something suspicious in the flat and try to look inside through the key hole and he saw a blood filled body of the old man.
CID arrived the scene.
On the outside of flat , he found two bottles of warm milk , Tuesday newspaper, some unopened mails , some gifts.
CID waste no time to find the murderer.
Who was the murderer ?
On Friday while delivering the mail , postman feels something suspicious in the flat and try to look inside through the key hole and he saw a blood filled body of the old man.
CID arrived the scene.
On the outside of flat , he found two bottles of warm milk , Tuesday newspaper, some unopened mails , some gifts.
CID waste no time to find the murderer.
Who was the murderer ?
Hint:
Newspaper delivery man was the murderer because of absence of Wednesday and Thursday missing newspaper.
This indicates he already know that there is no one to read it. Did you answer this riddle correctly?
YES NO
This indicates he already know that there is no one to read it. Did you answer this riddle correctly?
YES NO
Seconds In A Year Riddle
Hint:
Making Faces Riddle
When asked what he does all day, a man answered that he sits and makes faces. What does he really mean?
Hint:
From Begining To End Riddle
At the beginning of eternity,
At the end of space and time,
At the start of every end,
At the end of every place.
What am I?
At the end of space and time,
At the start of every end,
At the end of every place.
What am I?
Hint:
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