oh ran into that one before, it's hard one. Hint: Think binary
Here's an easy one, since the last one was hard:
Originally posted by: DrPizza
The king has 100 men in jail and is about to execute them. But, he tells them that the next morning, they will be lined up first & each will have a hat put on their heads, either a black hat, or a white hat. There won't necessarily be an equal number of each color. Each man will be facing forward, and will be able to see all of the hats in front of himself. But, he won't be able to see his own hat, nor the hats of those behind him. At execution time, the king is going to start at the back of the line and ask each man what color his hat is. If he's right, he lives. If he's wrong? He's put to death immediately. Any attempt at communication other than their guess of color on top of their heads will result in immediate execution of all the men. i.e. they may not change the tone or inflection of their voice, or signal in some other manner. They may only respond "White!" or "Black!" Each prisoner (except the dead ones) will be able to hear the colors the other prisoners have chosen.
What strategy can the prisoners use to maximize the number of prisoners that live?
for starters, if each even numbered prisoner simply states the color of the man's hat in front of him, that would guarantee that 50% of them lived; more every time two prisoners in a row shared the same color hat. Can you improve upon that strategy?
A farmer needs to take a fox, a chicken and a bag of seeds across a river in a small boat that will only hold one of them at a time. How can he do it in the least number of trips and not have the fox eat the chicken or the chicken eat the seeds?
Originally posted by: JTsyo
Originally posted by: DrPizza
The king has 100 men in jail and is about to execute them. But, he tells them that the next morning, they will be lined up first & each will have a hat put on their heads, either a black hat, or a white hat. There won't necessarily be an equal number of each color. Each man will be facing forward, and will be able to see all of the hats in front of himself. But, he won't be able to see his own hat, nor the hats of those behind him. At execution time, the king is going to start at the back of the line and ask each man what color his hat is. If he's right, he lives. If he's wrong? He's put to death immediately. Any attempt at communication other than their guess of color on top of their heads will result in immediate execution of all the men. i.e. they may not change the tone or inflection of their voice, or signal in some other manner. They may only respond "White!" or "Black!" Each prisoner (except the dead ones) will be able to hear the colors the other prisoners have chosen.
What strategy can the prisoners use to maximize the number of prisoners that live?
for starters, if each even numbered prisoner simply states the color of the man's hat in front of him, that would guarantee that 50% of them lived; more every time two prisoners in a row shared the same color hat. Can you improve upon that strategy?
oh ran into that one before, it's hard one. Hint: Think binary
Here's an easy one, since the last one was hard:
A farmer needs to take a fox, a chicken and a bag of seeds across a river in a small boat that will only hold one of them at a time. How can he do it in the least number of trips and not have the fox eat the chicken or the chicken eat the seeds?
Originally posted by: techs
Here's a classic from the All in the Family tv show:
A father and his son are in a car. The car goes off the road and hits a tree, killing the father and seriously injuring the son. An ambulance arrives and rushes the son to the emergency room. A doctor enters the emergency room, takes one look at the boy and says, "I can't operate on him. He's my son."
How can that be?
Originally posted by: marketsons1985
Originally posted by: DrPizza
The king has 100 men in jail and is about to execute them. But, he tells them that the next morning, they will be lined up first & each will have a hat put on their heads, either a black hat, or a white hat. There won't necessarily be an equal number of each color. Each man will be facing forward, and will be able to see all of the hats in front of himself. But, he won't be able to see his own hat, nor the hats of those behind him. At execution time, the king is going to start at the back of the line and ask each man what color his hat is. If he's right, he lives. If he's wrong? He's put to death immediately. Any attempt at communication other than their guess of color on top of their heads will result in immediate execution of all the men. i.e. they may not change the tone or inflection of their voice, or signal in some other manner. They may only respond "White!" or "Black!" Each prisoner (except the dead ones) will be able to hear the colors the other prisoners have chosen.
What strategy can the prisoners use to maximize the number of prisoners that live?
for starters, if each even numbered prisoner simply states the color of the man's hat in front of him, that would guarantee that 50% of them lived; more every time two prisoners in a row shared the same color hat. Can you improve upon that strategy?
Each prisoner says the color of the hat in front of them. THat way, only the back line has a 50% chance of living. The rest have 100% if they listen well. Sucks for the back of the line but....then you get 90+ living.
Originally posted by: Inspector Jihad
Originally posted by: marketsons1985
Originally posted by: DrPizza
The king has 100 men in jail and is about to execute them. But, he tells them that the next morning, they will be lined up first & each will have a hat put on their heads, either a black hat, or a white hat. There won't necessarily be an equal number of each color. Each man will be facing forward, and will be able to see all of the hats in front of himself. But, he won't be able to see his own hat, nor the hats of those behind him. At execution time, the king is going to start at the back of the line and ask each man what color his hat is. If he's right, he lives. If he's wrong? He's put to death immediately. Any attempt at communication other than their guess of color on top of their heads will result in immediate execution of all the men. i.e. they may not change the tone or inflection of their voice, or signal in some other manner. They may only respond "White!" or "Black!" Each prisoner (except the dead ones) will be able to hear the colors the other prisoners have chosen.
What strategy can the prisoners use to maximize the number of prisoners that live?
for starters, if each even numbered prisoner simply states the color of the man's hat in front of him, that would guarantee that 50% of them lived; more every time two prisoners in a row shared the same color hat. Can you improve upon that strategy?
Each prisoner says the color of the hat in front of them. THat way, only the back line has a 50% chance of living. The rest have 100% if they listen well. Sucks for the back of the line but....then you get 90+ living.
i don't understand your reasoning...maybe i'm not understanding what you're trying to get at but i think there is a flaw in your answer.
Originally posted by: DrPizza
The king has 100 men in jail and is about to execute them. But, he tells them that the next morning, they will be lined up first & each will have a hat put on their heads, either a black hat, or a white hat. There won't necessarily be an equal number of each color. Each man will be facing forward, and will be able to see all of the hats in front of himself. But, he won't be able to see his own hat, nor the hats of those behind him. At execution time, the king is going to start at the back of the line and ask each man what color his hat is. If he's right, he lives. If he's wrong? He's put to death immediately. Any attempt at communication other than their guess of color on top of their heads will result in immediate execution of all the men. i.e. they may not change the tone or inflection of their voice, or signal in some other manner. They may only respond "White!" or "Black!" Each prisoner (except the dead ones) will be able to hear the colors the other prisoners have chosen.
What strategy can the prisoners use to maximize the number of prisoners that live?
for starters, if each even numbered prisoner simply states the color of the man's hat in front of him, that would guarantee that 50% of them lived; more every time two prisoners in a row shared the same color hat. Can you improve upon that strategy?
Originally posted by: DrPizza
The king has 100 men in jail and is about to execute them. But, he tells them that the next morning, they will be lined up first & each will have a hat put on their heads, either a black hat, or a white hat. There won't necessarily be an equal number of each color. Each man will be facing forward, and will be able to see all of the hats in front of himself. But, he won't be able to see his own hat, nor the hats of those behind him. At execution time, the king is going to start at the back of the line and ask each man what color his hat is. If he's right, he lives. If he's wrong? He's put to death immediately. Any attempt at communication other than their guess of color on top of their heads will result in immediate execution of all the men. i.e. they may not change the tone or inflection of their voice, or signal in some other manner. They may only respond "White!" or "Black!" Each prisoner (except the dead ones) will be able to hear the colors the other prisoners have chosen.
What strategy can the prisoners use to maximize the number of prisoners that live?
for starters, if each even numbered prisoner simply states the color of the man's hat in front of him, that would guarantee that 50% of them lived; more every time two prisoners in a row shared the same color hat. Can you improve upon that strategy?
Originally posted by: mcurphy
Originally posted by: DrPizza
The king has 100 men in jail and is about to execute them. But, he tells them that the next morning, they will be lined up first & each will have a hat put on their heads, either a black hat, or a white hat. There won't necessarily be an equal number of each color. Each man will be facing forward, and will be able to see all of the hats in front of himself. But, he won't be able to see his own hat, nor the hats of those behind him. At execution time, the king is going to start at the back of the line and ask each man what color his hat is. If he's right, he lives. If he's wrong? He's put to death immediately. Any attempt at communication other than their guess of color on top of their heads will result in immediate execution of all the men. i.e. they may not change the tone or inflection of their voice, or signal in some other manner. They may only respond "White!" or "Black!" Each prisoner (except the dead ones) will be able to hear the colors the other prisoners have chosen.
What strategy can the prisoners use to maximize the number of prisoners that live?
for starters, if each even numbered prisoner simply states the color of the man's hat in front of him, that would guarantee that 50% of them lived; more every time two prisoners in a row shared the same color hat. Can you improve upon that strategy?
Does anyone have the answer for this one?
Originally posted by: Ornery Platypus
Originally posted by: Lithium381
the king one was easy, never heard i before though. reminds me of the two gatekeepers at a fork in the road. one path leads to eath, the other to paradise. now the gatekeepers, there is one who lies and one who always tells the truth, you only get to ask which path to take to one of them, how do you know which way to go?
Ask one of the gatekeepers which way the other would say to go. Take the opposite path.
Originally posted by: gdextreme
Originally posted by: Joemonkey
Originally posted by: gdextreme
12) There is a truck carrying a crane on the way to the city. On the way the truck driver sees a train bridge above the road. The truck has to pass under the bridge. The clearance sign before the bridge says that vehicles under the height of 3 metres or lower may cross safely. Now the truck driver knows that the truck's height including the crane is 3metres and 1 centimetre. There is no other route to the city. How does the truck driver manage to cross under the bridge without damaging the bridge?
Please ask for clarification if any part is not clear to you. Don't reply if you have solved it before.
deflate the tires, go under the bridge slowly, re-inflate the tires on the other side
Or he could just deflate the tires a little bit so that it lowers the height of the crane by 1cm + a bit more, but your idea works perfectly. Any more riddles anyone. I'm thinking of posting some riddles which require use of basic maths. Anyone interested in those?
Originally posted by: YOyoYOhowsDAjello
Originally posted by: gdextreme
Originally posted by: Joemonkey
Originally posted by: gdextreme
This is a picture of a moving bus. Which direction is the bus moving. Right or left? Please post reason. Don't reply if you have solved this puzzle before.
http://pics.bbzzdd.com/users/gdextreme/PUZZLE.jpg
to the left since you can't see the door that is on the right side of the bus
unless you're in the UK or something
Thats why the BOSTON BUS SERVICE Banner.
http://en.wikipedia.org/wiki/Boston,_Lincolnshire
Originally posted by: mcurphy
Originally posted by: DrPizza
The king has 100 men in jail and is about to execute them. But, he tells them that the next morning, they will be lined up first & each will have a hat put on their heads, either a black hat, or a white hat. There won't necessarily be an equal number of each color. Each man will be facing forward, and will be able to see all of the hats in front of himself. But, he won't be able to see his own hat, nor the hats of those behind him. At execution time, the king is going to start at the back of the line and ask each man what color his hat is. If he's right, he lives. If he's wrong? He's put to death immediately. Any attempt at communication other than their guess of color on top of their heads will result in immediate execution of all the men. i.e. they may not change the tone or inflection of their voice, or signal in some other manner. They may only respond "White!" or "Black!" Each prisoner (except the dead ones) will be able to hear the colors the other prisoners have chosen.
What strategy can the prisoners use to maximize the number of prisoners that live?
for starters, if each even numbered prisoner simply states the color of the man's hat in front of him, that would guarantee that 50% of them lived; more every time two prisoners in a row shared the same color hat. Can you improve upon that strategy?
Does anyone have the answer for this one?
Originally posted by: GrantMeThePower
Originally posted by: mcurphy
Originally posted by: DrPizza
The king has 100 men in jail and is about to execute them. But, he tells them that the next morning, they will be lined up first & each will have a hat put on their heads, either a black hat, or a white hat. There won't necessarily be an equal number of each color. Each man will be facing forward, and will be able to see all of the hats in front of himself. But, he won't be able to see his own hat, nor the hats of those behind him. At execution time, the king is going to start at the back of the line and ask each man what color his hat is. If he's right, he lives. If he's wrong? He's put to death immediately. Any attempt at communication other than their guess of color on top of their heads will result in immediate execution of all the men. i.e. they may not change the tone or inflection of their voice, or signal in some other manner. They may only respond "White!" or "Black!" Each prisoner (except the dead ones) will be able to hear the colors the other prisoners have chosen.
What strategy can the prisoners use to maximize the number of prisoners that live?
for starters, if each even numbered prisoner simply states the color of the man's hat in front of him, that would guarantee that 50% of them lived; more every time two prisoners in a row shared the same color hat. Can you improve upon that strategy?
Does anyone have the answer for this one?
I think the way it would have to work would go something like this:
If there are more than one hats in a row in front of a prisoner that are the same color, then the prisoner says black. He then has a 50/50 chance of surviving.
The person in front of him, however, will see the hat in front of him. If that person's hat is white, he says white (knowing that there were more than one before the last guy that was the same color). He would have a 100% chance of survival. The person in front of HIM would ALSO know, then that he has a white hat. He also has a 100% chance of survival. The person in front of him, though, can not be sure what to do and reverts to the previous "unknown" state, and says black if there are more than one hats in a row of the same color, or says white, if the next two hats are different.
In other words, every 3rd person has a 50% chance of survival, and the other 66.66% have a 100% chance of survival.
1-(.5x.3333)= 83.33% of the people live.
Originally posted by: marketsons1985
Originally posted by: DrPizza
The king has 100 men in jail and is about to execute them. But, he tells them that the next morning, they will be lined up first & each will have a hat put on their heads, either a black hat, or a white hat. There won't necessarily be an equal number of each color. Each man will be facing forward, and will be able to see all of the hats in front of himself. But, he won't be able to see his own hat, nor the hats of those behind him. At execution time, the king is going to start at the back of the line and ask each man what color his hat is. If he's right, he lives. If he's wrong? He's put to death immediately. Any attempt at communication other than their guess of color on top of their heads will result in immediate execution of all the men. i.e. they may not change the tone or inflection of their voice, or signal in some other manner. They may only respond "White!" or "Black!" Each prisoner (except the dead ones) will be able to hear the colors the other prisoners have chosen.
What strategy can the prisoners use to maximize the number of prisoners that live?
for starters, if each even numbered prisoner simply states the color of the man's hat in front of him, that would guarantee that 50% of them lived; more every time two prisoners in a row shared the same color hat. Can you improve upon that strategy?
Each prisoner says the color of the hat in front of them. THat way, only the back line has a 50% chance of living. The rest have 100% if they listen well. Sucks for the back of the line but....then you get 90+ living.
Originally posted by: s0ssos
Originally posted by: GrantMeThePower
Originally posted by: mcurphy
Originally posted by: DrPizza
The king has 100 men in jail and is about to execute them. But, he tells them that the next morning, they will be lined up first & each will have a hat put on their heads, either a black hat, or a white hat. There won't necessarily be an equal number of each color. Each man will be facing forward, and will be able to see all of the hats in front of himself. But, he won't be able to see his own hat, nor the hats of those behind him. At execution time, the king is going to start at the back of the line and ask each man what color his hat is. If he's right, he lives. If he's wrong? He's put to death immediately. Any attempt at communication other than their guess of color on top of their heads will result in immediate execution of all the men. i.e. they may not change the tone or inflection of their voice, or signal in some other manner. They may only respond "White!" or "Black!" Each prisoner (except the dead ones) will be able to hear the colors the other prisoners have chosen.
What strategy can the prisoners use to maximize the number of prisoners that live?
for starters, if each even numbered prisoner simply states the color of the man's hat in front of him, that would guarantee that 50% of them lived; more every time two prisoners in a row shared the same color hat. Can you improve upon that strategy?
Does anyone have the answer for this one?
I think the way it would have to work would go something like this:
If there are more than one hats in a row in front of a prisoner that are the same color, then the prisoner says black. He then has a 50/50 chance of surviving.
The person in front of him, however, will see the hat in front of him. If that person's hat is white, he says white (knowing that there were more than one before the last guy that was the same color). He would have a 100% chance of survival. The person in front of HIM would ALSO know, then that he has a white hat. He also has a 100% chance of survival. The person in front of him, though, can not be sure what to do and reverts to the previous "unknown" state, and says black if there are more than one hats in a row of the same color, or says white, if the next two hats are different.
In other words, every 3rd person has a 50% chance of survival, and the other 66.66% have a 100% chance of survival.
1-(.5x.3333)= 83.33% of the people live.
obviously in real life it wouldn't work so easily. because some people would have to "take one for the team". as in, they wouldn't get any help from anybody else (the every other person in the first case, and every 3rd person in this case). and nobody likes giving up their life for nothing in return (nor do most people sacrifice their lives to save others).
HOWEVER, the question is whether or not their chance of survival is 50%. and i would venture to say no. let's say in the first scenario (where every other person says the color in front of them), the guy in front of you is white, so you have to say white. but your hat is black. then you die. 100% of the time. so anytime a pair differs in color, the one who has to say the color in front of him dies. so, it is not a 50% chance anymore. it is a less than 50% chance, but not so easy to calculate. and the same goes with the other case.
so, that means the total probability of people that will live is incorrect, in all these answers.
Originally posted by: TuxDave
Originally posted by: mcurphy
Originally posted by: DrPizza
The king has 100 men in jail and is about to execute them. But, he tells them that the next morning, they will be lined up first & each will have a hat put on their heads, either a black hat, or a white hat. There won't necessarily be an equal number of each color. Each man will be facing forward, and will be able to see all of the hats in front of himself. But, he won't be able to see his own hat, nor the hats of those behind him. At execution time, the king is going to start at the back of the line and ask each man what color his hat is. If he's right, he lives. If he's wrong? He's put to death immediately. Any attempt at communication other than their guess of color on top of their heads will result in immediate execution of all the men. i.e. they may not change the tone or inflection of their voice, or signal in some other manner. They may only respond "White!" or "Black!" Each prisoner (except the dead ones) will be able to hear the colors the other prisoners have chosen.
What strategy can the prisoners use to maximize the number of prisoners that live?
for starters, if each even numbered prisoner simply states the color of the man's hat in front of him, that would guarantee that 50% of them lived; more every time two prisoners in a row shared the same color hat. Can you improve upon that strategy?
ah! yours is even better than mine. that is a 99.5% survival for the group.
Does anyone have the answer for this one?
I do, and for those who still want to work it out, don't read this.
The System:
Guy in the back will say black if there are an odd number of black hats he sees. He has a 50/50 chance of dying.
Next guy goes and sees how many black hats he sees. If there are an even number of hats in front of him and the guy behind him saw an odd number, he knows he has a black hat and says black and goes free. This works for all other cases that if he sees the same odd/even then he knows he's wearing a white one etc...
Next guy see how many black hats are in front of him. He can also figure out how many hats the previous person would've seen (odd/even). For example. Last guy said black (he saw odd). Next guy says black (he must've seen even or else we would've called white). And now that he knows the previous guy saw an even number and he sees how many is in front of him, he can guess what he has.
and repeat... everyone lives except the last guy in the line which has a 50/50 chance of dying. Hence my whole "parity" clue I gave above.
Originally posted by: GrantMeThePower
Originally posted by: TuxDave
Originally posted by: mcurphy
Originally posted by: DrPizza
The king has 100 men in jail and is about to execute them. But, he tells them that the next morning, they will be lined up first & each will have a hat put on their heads, either a black hat, or a white hat. There won't necessarily be an equal number of each color. Each man will be facing forward, and will be able to see all of the hats in front of himself. But, he won't be able to see his own hat, nor the hats of those behind him. At execution time, the king is going to start at the back of the line and ask each man what color his hat is. If he's right, he lives. If he's wrong? He's put to death immediately. Any attempt at communication other than their guess of color on top of their heads will result in immediate execution of all the men. i.e. they may not change the tone or inflection of their voice, or signal in some other manner. They may only respond "White!" or "Black!" Each prisoner (except the dead ones) will be able to hear the colors the other prisoners have chosen.
What strategy can the prisoners use to maximize the number of prisoners that live?
for starters, if each even numbered prisoner simply states the color of the man's hat in front of him, that would guarantee that 50% of them lived; more every time two prisoners in a row shared the same color hat. Can you improve upon that strategy?
ah! yours is even better than mine. that is a 99.5% survival for the group.
Does anyone have the answer for this one?
I do, and for those who still want to work it out, don't read this.
The System:
Guy in the back will say black if there are an odd number of black hats he sees. He has a 50/50 chance of dying.
Next guy goes and sees how many black hats he sees. If there are an even number of hats in front of him and the guy behind him saw an odd number, he knows he has a black hat and says black and goes free. This works for all other cases that if he sees the same odd/even then he knows he's wearing a white one etc...
Next guy see how many black hats are in front of him. He can also figure out how many hats the previous person would've seen (odd/even). For example. Last guy said black (he saw odd). Next guy says black (he must've seen even or else we would've called white). And now that he knows the previous guy saw an even number and he sees how many is in front of him, he can guess what he has.
and repeat... everyone lives except the last guy in the line which has a 50/50 chance of dying. Hence my whole "parity" clue I gave above.
edit-
weird. what i wrote didnt come through
anyway, yeah your solution is even better than mine. yours is 99.5% survival for the group.
Originally posted by: tk149
Originally posted by: nanobreath
Heres one:
A man lives on the top floor of a 50 story building. When he leaves he takes the elevator to the first floor and leaves. When he returns, however, he takes the elevator up to the 10th floor, but has to use the stairs for the remainder of the trip. The elevator is in perfect functioning condition when he takes the stairs. He doesn't take the stairs because he wants to, but because he has no choice. Plenty of other people take the elevator up further, and nobody is forcing him to use the stairs. Nevertheless, he has no choice in the matter and must take the stairs past the 10th floor if he rides alone. Why?
You left out the part about when it's raining, he takes the elevator all the way up.
Originally posted by: marketsons1985
Originally posted by: DrPizza
The king has 100 men in jail and is about to execute them. But, he tells them that the next morning, they will be lined up first & each will have a hat put on their heads, either a black hat, or a white hat. There won't necessarily be an equal number of each color. Each man will be facing forward, and will be able to see all of the hats in front of himself. But, he won't be able to see his own hat, nor the hats of those behind him. At execution time, the king is going to start at the back of the line and ask each man what color his hat is. If he's right, he lives. If he's wrong? He's put to death immediately. Any attempt at communication other than their guess of color on top of their heads will result in immediate execution of all the men. i.e. they may not change the tone or inflection of their voice, or signal in some other manner. They may only respond "White!" or "Black!" Each prisoner (except the dead ones) will be able to hear the colors the other prisoners have chosen.
What strategy can the prisoners use to maximize the number of prisoners that live?
for starters, if each even numbered prisoner simply states the color of the man's hat in front of him, that would guarantee that 50% of them lived; more every time two prisoners in a row shared the same color hat. Can you improve upon that strategy?
Each prisoner says the color of the hat in front of them. THat way, only the back line has a 50% chance of living. The rest have 100% if they listen well. Sucks for the back of the line but....then you get 90+ living.
Yeah seriously, these are no longer riddles, at least not to anyone who was born and raised after the sexual revolution of the 1970's.Originally posted by: gdextreme
I've heard of this one too. Similar to one already posted.Originally posted by: techs
Here's a classic from the All in the Family tv show:
A father and his son are in a car. The car goes off the road and hits a tree, killing the father and seriously injuring the son. An ambulance arrives and rushes the son to the emergency room. A doctor enters the emergency room, takes one look at the boy and says, "I can't operate on him. He's my son."
How can that be?
Originally posted by: Joemonkey
Originally posted by: gdextreme
This is a picture of a moving bus. Which direction is the bus moving. Right or left? Please post reason. Don't reply if you have solved this puzzle before.
http://pics.bbzzdd.com/users/gdextreme/PUZZLE.jpg
to the left since you can't see the door that is on the right side of the bus
unless you're in the UK or something
Originally posted by: nanobreath
Heres one:
A man lives on the top floor of a 50 story building. When he leaves he takes the elevator to the first floor and leaves. When he returns, however, he takes the elevator up to the 10th floor, but has to use the stairs for the remainder of the trip. The elevator is in perfect functioning condition when he takes the stairs. He doesn't take the stairs because he wants to, but because he has no choice. Plenty of other people take the elevator up further, and nobody is forcing him to use the stairs. Nevertheless, he has no choice in the matter and must take the stairs past the 10th floor if he rides alone. Why?
Originally posted by: gdextreme
10) There are 6 apples in a basket kept on a table inside a room. After every 10 minutes a girl comes into the room and takes one apple with her. After the sixth girl leaves the room, there is still an apple left in the basket. How is this possible?
Originally posted by: 2Xtreme21
Originally posted by: JTsyo
Originally posted by: DrPizza
The king has 100 men in jail and is about to execute them. But, he tells them that the next morning, they will be lined up first & each will have a hat put on their heads, either a black hat, or a white hat. There won't necessarily be an equal number of each color. Each man will be facing forward, and will be able to see all of the hats in front of himself. But, he won't be able to see his own hat, nor the hats of those behind him. At execution time, the king is going to start at the back of the line and ask each man what color his hat is. If he's right, he lives. If he's wrong? He's put to death immediately. Any attempt at communication other than their guess of color on top of their heads will result in immediate execution of all the men. i.e. they may not change the tone or inflection of their voice, or signal in some other manner. They may only respond "White!" or "Black!" Each prisoner (except the dead ones) will be able to hear the colors the other prisoners have chosen.
What strategy can the prisoners use to maximize the number of prisoners that live?
for starters, if each even numbered prisoner simply states the color of the man's hat in front of him, that would guarantee that 50% of them lived; more every time two prisoners in a row shared the same color hat. Can you improve upon that strategy?
oh ran into that one before, it's hard one. Hint: Think binary
Here's an easy one, since the last one was hard:
A farmer needs to take a fox, a chicken and a bag of seeds across a river in a small boat that will only hold one of them at a time. How can he do it in the least number of trips and not have the fox eat the chicken or the chicken eat the seeds?
- Take chicken to other side.
- Come back, pick up fox, take to other side.
- Pick up chicken, take back to original side.
- Pick up seeds, take to other side.
- Go back, pick up chicken.