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 Safest Place Riddle
Hint:
Aliens Favorite Place On A Computer Riddle
Hint:
I Shave Everyday Riddle
Hint:
The Start Of Nothing Logic Riddle
Hint: It's in plain sight
Staying In Place Riddle
Hint:
What Begins With T Riddle
Hint:
A Word Referring To Women Riddle
Hint:
Plates In Space
Hint:
Santa And A Space Ship
Hint:
Begins With L Riddle
Begins with L and ends with Y
With its presence relationships survive
Through slightest inkling of its loss
Instant separation can be caused.
What is it?
With its presence relationships survive
Through slightest inkling of its loss
Instant separation can be caused.
What is it?
Hint:
This Gate's Key Riddle
My first is foremost legally,
My second circles outwardly,
My third leads all in victory,
My fourth twice ends a nominee,
My whole is this gate's only key.
What am I?
My second circles outwardly,
My third leads all in victory,
My fourth twice ends a nominee,
My whole is this gate's only key.
What am I?
Hint:
Egg In A Glass Riddle
A science teacher told his after school class, "Whoever can get this egg into this smaller glass bottle will win no homework for a week! The rules are: the egg has to go into the bottle in one piece, and you can't break the bottle. You can also use anything in the science lab. So, do we have any volunteers?"
A boy raised his hand and the teacher pointed at him. The boy took the egg and looked around the science lab for the things he could use. He saw some writing paper, a pack of matches, some vinegar, a sink, and the glass bottle. By the end of the after school class, the boy had gotten the egg into the smaller bottle.
How did he do it?
A boy raised his hand and the teacher pointed at him. The boy took the egg and looked around the science lab for the things he could use. He saw some writing paper, a pack of matches, some vinegar, a sink, and the glass bottle. By the end of the after school class, the boy had gotten the egg into the smaller bottle.
How did he do it?
Hint: Without doing anything to the egg, the egg can't fit into the bottle
First, soak the egg in the vinegar which softens the shell without compromising the egg. Next, take some of the writing paper and shred it into pieces. Take the shredded pieces and put them into the glass bottle. Take a match and light a fire inside the bottle with the shredded paper. After, take the vinegar-soaked egg and put it on the top of the bottle so no oxygen can get into the bottle. The fire can't live without any oxygen so it will try to suck oxygen from the entrance which the egg is blocking. When the fire does this, the fire becomes like a vacuum. So, basically, the fire sucks the egg into the bottle to try to get the oxygen. After a short while, the shell will reharden and that's how the egg got into the bottle. Did you answer this riddle correctly?
YES NO
YES NO
Red Dusty Planet Riddle
If you go to outer space
And head away from the sun
The first planet you would reach
Would be this red, dusty one
Which planet is it?
And head away from the sun
The first planet you would reach
Would be this red, dusty one
Which planet is it?
Hint:
Not A Fairground Ride
It spins at 1,000 miles per hour
Although it is not a fairground ride
At its center there is a molten core
And it has a crust on its outside
What is it?
Although it is not a fairground ride
At its center there is a molten core
And it has a crust on its outside
What is it?
Hint:
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