Flip The Switch Riddle
There is a prison with 100 prisoners, each in separate cells with no form of contact. There is an area in the prison with a single light bulb in it. Each day, the warden picks one of the prisoners at random, even if they have been picked before, and takes them out to the lobby. The prisoner will have the choice to flip the switch if they want. The light bulb starts off.
When a prisoner is taken into the area with the light bulb, he can also say "Every prisoner has been brought to the light bulb." If this is true all prisoners will go free. However, if a prisoner chooses to say this and it's wrong, all the prisoners will be executed. So a prisoner should only say this if he knows it is true for sure.
Before the first day of this process begins, all the prisoners are allowed to get together to discuss a strategy to eventually save themselves.
What strategy could they use to ensure they will go free?
When a prisoner is taken into the area with the light bulb, he can also say "Every prisoner has been brought to the light bulb." If this is true all prisoners will go free. However, if a prisoner chooses to say this and it's wrong, all the prisoners will be executed. So a prisoner should only say this if he knows it is true for sure.
Before the first day of this process begins, all the prisoners are allowed to get together to discuss a strategy to eventually save themselves.
What strategy could they use to ensure they will go free?
Hint:
Only allow one prisoner to turn the light bulb off and all of the others turn it on if they have never turned it on before. If they have turned it on before they do nothing. The prisoner that can turn it off then knows they have all been there and saves them all when he has turned it off 99 times. Did you answer this riddle correctly?
YES NO
YES NO
How Do You Survive Riddle
Your father is a scientist who has invented a red pill which, if eaten with 1 blue pill which he has invented, will grant immortality. The night he invents it, he gives you 2 red and 2 blue pills just in case one of them is lost or substandard. He also warns you that an overdose will cause the opposite effect and kill you instead.
You put the pills in your pocket and leave his lab for home. On the way home, you are abducted by aliens who blindfold you and throw you into a singularity. At this point, you remember the pills your father gave you. You take them out (you can move and have enough oxygen in space for a short time), but realize that you can't tell the red pill from the blue pill. Even if you take off your blindfold, you can't see anything due to your proximity to the black hole. Given the circumstances, how do you successfully eat 1 red and 1 blue pill and survive?
You put the pills in your pocket and leave his lab for home. On the way home, you are abducted by aliens who blindfold you and throw you into a singularity. At this point, you remember the pills your father gave you. You take them out (you can move and have enough oxygen in space for a short time), but realize that you can't tell the red pill from the blue pill. Even if you take off your blindfold, you can't see anything due to your proximity to the black hole. Given the circumstances, how do you successfully eat 1 red and 1 blue pill and survive?
Hint:
Coffee Diner Riddle
A man walks into a diner and sits down. There's a new waitress working that he's never seen before. When she comes to his table to take his order, he says "Just a cup of coffee please." A few minutes later the waitress brings the man his coffee and heads back to the kitchen. A short while later, the man notices that there is a fly in his coffee and calls the waitress back. He asks her nicely to bring him another cup. The waitress brings the man's cup of coffee back to the kitchen and returns a few moments later. "Here you are, I poured you a new cup of coffee, no fly this time" she says and hands him the cup. The waitress turns around and starts to head back to the kitchen. She only takes a few steps before she hears the man shout out "Hey, this is the same cup of coffee, all you did was remove the fly!"
Assuming the coffee was still hot, how did the man know it was the same cup of coffee?
Assuming the coffee was still hot, how did the man know it was the same cup of coffee?
Hint: A man walks into a diner and sits down. There's a new waitress working that he's never seen before. When she comes to his table to take his order, he says "Just a cup of coffee please." A few minutes later the waitress brings the man his coffee and heads
Because the coffee was sweet. The man had added sugar to his coffee before noticing the fly. When the waitress brought him the "new" cup of coffee, he took a sip (to check whether it was in fact a newly poured cup of coffee) and noticed that the coffee was "already" sweet. Did you answer this riddle correctly?
YES NO
YES NO
The Color On Top Riddle
When youre driving in a car
This color is on top
Of a set of traffic lights
It means that you should stop.
This color is..?
This color is on top
Of a set of traffic lights
It means that you should stop.
This color is..?
Hint:
Shipwrecked And Alone Riddle
There is one of these called Easter
With statues of faces made of stone
If you were on a desert one
Youre probably shipwrecked and alone.
Where are you?
With statues of faces made of stone
If you were on a desert one
Youre probably shipwrecked and alone.
Where are you?
Hint:
As Long As A Football Field Riddle
Yet I fit in the palm of your hand.
I will make you bleed if you dont use me often.
You put me in your mouth but dont eat me,
Then you throw me away.
What am I?
Hint:
Floss. It typically comes in 100 yard packs, which fit easily in your hand. If you dont floss regularly, your gums will bleed. You use floss in your mouth then throw it away when youre done. Did you answer this riddle correctly?
YES NO
YES NO
Lasting Memories Riddle
I make memories that last a lifetime,
Without me youll be miserable,
If you miss me you can gourge and its okay.
Some say I am naturally split in two.
What am I?
Without me youll be miserable,
If you miss me you can gourge and its okay.
Some say I am naturally split in two.
What am I?
Hint:
Sleep. Its the time your mind organizes memories and knowledge. Sleep deprivation is miserable (as you well know if youve experienced it). If you miss a few nights of sleep, you can sleep more to catch up with no problems. And some believe that segmented sleep, where you sleep, wake for an hour, then go back to sleep, was the dominant form of sleep before the Industrial Revolution. Did you answer this riddle correctly?
YES NO
YES NO
The Dogwood Tree Riddle
Hint:
You Have To Give It Riddle
You can only have it once you have given it. And when you have it, it takes noble effort to maintain it.
Hint:
Marrying The Princess Riddle
A king wants his daughter to marry the smartest of 3 extremely intelligent young princes, and so the king's wise men devised an intelligence test.
The princes are gathered into a room and seated, facing one another, and are shown 2 black hats and 3 white hats. They are blindfolded, and 1 hat is placed on each of their heads, with the remaining hats hidden in a different room.
The king tells them that the first prince to deduce the color of his hat without removing it or looking at it will marry his daughter. A wrong guess will mean death. The blindfolds are then removed.
You are one of the princes. You see 2 white hats on the other prince's heads. After some time you realize that the other prince's are unable to deduce the color of their hat, or are unwilling to guess. What color is your hat?
The princes are gathered into a room and seated, facing one another, and are shown 2 black hats and 3 white hats. They are blindfolded, and 1 hat is placed on each of their heads, with the remaining hats hidden in a different room.
The king tells them that the first prince to deduce the color of his hat without removing it or looking at it will marry his daughter. A wrong guess will mean death. The blindfolds are then removed.
You are one of the princes. You see 2 white hats on the other prince's heads. After some time you realize that the other prince's are unable to deduce the color of their hat, or are unwilling to guess. What color is your hat?
Hint: You know that your competitors are very intelligent and want nothing more than to marry the princess. You also know that the king is a man of his word, and he has said that the test is a fair test of intelligence and bravery.
Answer: White.
The king would not select two white hats and one black hat. This would mean two princes would see one black hat and one white hat. You would be at a disadvantage if you were the only prince wearing a black hat.
If you were wearing the black hat, it would not take long for one of the other princes to deduce he was wearing a white hat.
If an intelligent prince saw a white hat and a black hat, he would eventually realize that the king would never select two black hats and one white hat. Any prince seeing two black hats would instantly know he was wearing a white hat. Therefore if a prince can see one black hat, he can work out he is wearing white.
Therefore the only fair test is for all three princes to be wearing white hats. After waiting some time just to be sure, you can safely assert you are wearing a white hat. Did you answer this riddle correctly?
YES NO
The king would not select two white hats and one black hat. This would mean two princes would see one black hat and one white hat. You would be at a disadvantage if you were the only prince wearing a black hat.
If you were wearing the black hat, it would not take long for one of the other princes to deduce he was wearing a white hat.
If an intelligent prince saw a white hat and a black hat, he would eventually realize that the king would never select two black hats and one white hat. Any prince seeing two black hats would instantly know he was wearing a white hat. Therefore if a prince can see one black hat, he can work out he is wearing white.
Therefore the only fair test is for all three princes to be wearing white hats. After waiting some time just to be sure, you can safely assert you are wearing a white hat. Did you answer this riddle correctly?
YES NO
100 Widgets Riddle
Hint:
It would take 5 minutes. Each machine takes 5 minutes to make its widget. Therefore, each of the 100 machines would have finished making its widget in 5 minutes. Did you answer this riddle correctly?
YES NO
YES NO
Presidential Slugger Riddle
Hint:
Cooking And Eating Riddle
You throw away the outside and cook the inside. Then you eat the outside and throw away the inside. What did you eat?
Hint:
Unlikely To See Trees Riddle
This is an area with little rain
So youre unlikely to see many trees
Kalahari, Negev, Atacama
Gobi and Sahara what are all these?
So youre unlikely to see many trees
Kalahari, Negev, Atacama
Gobi and Sahara what are all these?
Hint:
Pills A And B Riddle
You have two bottles of pills marked with the label A and B. The pills are identical. The doctor has asked you to take one A pill and one B pill daily. You cant take more or less than that.
While taking out the pills one day, you took out one pill from A and by mistake took out two from B. You have no idea which pill is which now.
You cant throw away the expensive pills. What will you do now?
While taking out the pills one day, you took out one pill from A and by mistake took out two from B. You have no idea which pill is which now.
You cant throw away the expensive pills. What will you do now?
Hint:
Cut each of the three pills in half and put each half in two piles. Now, each of the two piles will contain half of pill A and two halves of pill B.
Take one pill A and cut into half and put the two halves in the two piles. Now, each pile will have two halves of pill A and two halves of pill B which means one pill A and one pill B. You can take one pile today and one pile the next day. Did you answer this riddle correctly?
YES NO
Take one pill A and cut into half and put the two halves in the two piles. Now, each pile will have two halves of pill A and two halves of pill B which means one pill A and one pill B. You can take one pile today and one pile the next day. Did you answer this riddle correctly?
YES NO
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