Fastening Two People
Hint:
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 Same Birthday Riddle
How many people must be gathered together in a room, before you can be certain that there is a greater than 50/50 chance that at least two of them have the same birthday?
Hint:
Only twenty-three people need be in the room, a surprisingly small number. The probability that there will not be two matching birthdays is then, ignoring leap years, 365x364x363x...x343/365 over 23 which is approximately 0.493. this is less than half, and therefore the probability that a pair occurs is greater than 50-50. With as few as fourteen people in the room the chances are better than 50-50 that a pair will have birthdays on the same day or on consecutive days. Did you answer this riddle correctly?
YES NO
YES NO
The Prime Number Riddle
Two hundred people in an auditorium are asked to think of a single digit number from 1 to 9 inclusive and write it down. All those who wrote down a prime number are now asked to leave. Ninety people remain behind in the hall. How many of these are expected to have written down an odd number?
Hint: Remember that 1 is not a prime number.
Those that remain behind must have written {1,4,6,8,9} and from this only {1,9} are odd. The probability of an odd number is thus 2/5.
Expected number of odds is 2/5 * 90 = 36 Did you answer this riddle correctly?
YES NO
Expected number of odds is 2/5 * 90 = 36 Did you answer this riddle correctly?
YES NO
Fat And Flat Riddle
I'm flat when I'm new. I'm fat when you use me. I release my gas when something sharp touches me. What am I?
Hint:
Catching A Bullet Riddle
Alan fires a bullet from his hand gun and his friend Wade catches the bullet with his bare hands. The gun shoots actual, deadly bullets. The bullet does not touch anything but air after it leaves the gun and until it reaches Wades hand. Wade is uninjured. How does he do it?
Hint:
Alan fires his bullet from a .25 ACP (Automatic Colt Pistol), which will reach a maximum height of 2,287 feet. He shoots directly upward while standing at the base of Burj Khalifa, a 2,722 foot tall building.
Wade is a window cleaner at that building, waiting at 2,287 feet. When the bullet reaches that height and is about to go back down again, he reaches out with his bare hands and catches it. Did you answer this riddle correctly?
YES NO
Wade is a window cleaner at that building, waiting at 2,287 feet. When the bullet reaches that height and is about to go back down again, he reaches out with his bare hands and catches it. Did you answer this riddle correctly?
YES NO
I Kill People
I kill people when you need me to, I am not accepted and illegal, I need to be refilled from time to time and I can harm my owner. What am I?
Hint:
Share The Same Name Riddle
but mean two different things
one goes up and down
and the other spins
while one can make you sick
the other you cannot touch
you have heard of me before
whether you know it or not
you know our name
just give it a thought
One is a messenger
the other is not
One gives you a reading
The other helps the Oracle
What are we?
Hint:
Mercury (Messenger is Hermes, or in Latin it is Mercury) Did you answer this riddle correctly?
YES NO
YES NO
7B91011 Riddle
Mrs. Barbara Whitcombe, Ray's wife
Mr. Jason McCubbins, Ray's business partner
Mr. Harold Nichols, Ray's best friend
All three visited Mr. Whitcombe the day of his murder, but all three provided the police with stories of explanation as to the reason for their visit.
Police found Mr. Whitcombe with his wrist watch still on his right arm, a torn up picture of his wife laying on the floor beside the trash can, and an ink pen in his right hand. On the desk, the police found a name plate, a telephone that was off the hook, and a personal calendar turned to the July 5th page with 7B91011 written on it. After examining this evidence, the police knew their suspect.
Who was it?
Hint:
Jason McCubbins, Ray's business partner.
The calendar was the clue to solving this murder. The police realized that since Mr. Whitcombe was wearing his watch on his right arm, he must have been left-handed. Realizing that the number on the calendar was written in a hurry and with his opposite hand, police matched the written number with the months of the year. So the B was an 8, thereby giving us 7-8-9-10-11: July, August, September, October, November. Use the first letter of each month and it spells J-A-S-O-N. Did you answer this riddle correctly?
YES NO
The calendar was the clue to solving this murder. The police realized that since Mr. Whitcombe was wearing his watch on his right arm, he must have been left-handed. Realizing that the number on the calendar was written in a hurry and with his opposite hand, police matched the written number with the months of the year. So the B was an 8, thereby giving us 7-8-9-10-11: July, August, September, October, November. Use the first letter of each month and it spells J-A-S-O-N. Did you answer this riddle correctly?
YES NO
Peanut Butter And Cereal Riddle
Hint:
Mark And Nancy Riddle
On a Saturday afternoon, the couple went out to a restaurant to celebrate their fifth anniversary together. Her when they returned in the evening, they found their son dead. There were three other people in the house at the time of the murder. The babysitter said she was ironing sams school uniform for tomorrow. The maid said she was cleaning the corners of the house and the chef said he was chopping vegetables for dinner. Youve been hired to investigate who killed Sam. So who did it?
Hint:
It can be the babysitter or the chef.
Explanation: Both of them are the culprit because if they went for dinner so why the chef is preparing dinner?
And the other is the babysitter because she was ironing the shirt for school tomorrow but it was a Saturday so the next day is Sunday. Did you answer this riddle correctly?
YES NO
Explanation: Both of them are the culprit because if they went for dinner so why the chef is preparing dinner?
And the other is the babysitter because she was ironing the shirt for school tomorrow but it was a Saturday so the next day is Sunday. Did you answer this riddle correctly?
YES NO
McDonalds Riddle
Hint: The key is to first determine how much each item is worth. The drink is clearly worth 10, and it's apparent from the second line that the burgers are worth five.
Pictures of the fries are each worth two, but you have to keep in mind that each individual packet of fries is worth one when you get to the next line. That has baited people into thinking, incorrectly, that the last line is 5 + 2 x 10.
The fourth line has also thrown many people off because it involves order of operations after already including the tricky single packet of fries.
Multiplication comes before addition, so you have to multiply one packet of fries by one drink and then add that to one burger. Thus, 5 + (1x10) = 15. Did you answer this riddle correctly?
YES NO
The fourth line has also thrown many people off because it involves order of operations after already including the tricky single packet of fries.
Multiplication comes before addition, so you have to multiply one packet of fries by one drink and then add that to one burger. Thus, 5 + (1x10) = 15. Did you answer this riddle correctly?
YES NO
A Feeling That Cannot Be Touched
I am a feeling that cannot be touched,
But I'm more valuable than gold or clutch.
I'm a force that's strong, yet soft as a dove,
And I'm the reason behind every love.
You can't see me, but you feel me so true,
I'm what makes me say "I love you".
What am I?
But I'm more valuable than gold or clutch.
I'm a force that's strong, yet soft as a dove,
And I'm the reason behind every love.
You can't see me, but you feel me so true,
I'm what makes me say "I love you".
What am I?
Hint: Heart
Five Apples Riddle
Hint:
The fifth woman took the entire basket, with the apple still in it. Did you answer this riddle correctly?
YES NO
YES NO
Rivers With No Water Riddle
Hint: I represent an area of land or sea.
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