Brain Teasers
Three Gunmen
There are three gunmen on horses. Ab has a 100% chance of hitting his target when he shoots, but has a weak gun. He never misses. Bob also has a 100% chance of hitting, but he has a tremendous strong gun. However, Cam only has a 50% chance of hitting with his musket. Simultaneously, they all take a shot. One man is left alive. Who?
Hint
If you know you and another person shoot their target perfectly, who would you go for first?Answer
Cam is. The two other men, knowing they each shoot perfectly, would shoot each other knowing they still have a chance of surviving if Cam shoots at them. Nobody was shooting at Cam, therefore, he stays alive.Hide Hint Show Hint Hide Answer Show Answer
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This was fun to think through; thanks!
BUT! I don't think you are using logic. You suggest one course of action, but it is simply a presumption.
I think A and B would be silly to aim for each other as they know they will both be killed. It is more likely that they both aim for C. Thus C will be shot and each of A and B has only a 25% chance of being shot. This seems logical to me, but it is still presumption, not logic.
In my scenario, C managed to hit his target, but we can not know who was left alive.
BUT! I don't think you are using logic. You suggest one course of action, but it is simply a presumption.
I think A and B would be silly to aim for each other as they know they will both be killed. It is more likely that they both aim for C. Thus C will be shot and each of A and B has only a 25% chance of being shot. This seems logical to me, but it is still presumption, not logic.
In my scenario, C managed to hit his target, but we can not know who was left alive.
dalfamnest is right!
But honestly, why wouldyou shoot Cam? If you did that, then the other person would probably shoot you, and you know you'd be dead. Get rid of the competition.
Andin addition, dalamfest,he would shoot for B most likely because he has a stronger gun.
The true question is: Why are they shooting each other? But I always ask questions like that. Good teaser, even though it was pretty easy. You just gotta know what you would probably do in each guy's position.
@dalfamnest .. I think the solution is quite logical.. Cam will be the one alive. Firstly it is reasonable to assume that after an initial calculation of survival probabilities, they shoot away immediately and not wait till they point guns at each other. If Ab doesn't know who Bob will shoot, killing off Bob would give him a 75% chance of survival against Bob choosing Ab randomly and shooting him which would give him a 50% chance of survival. Same logic applies for Bob. Hence they shoot each other.
Great teaser even though a bit easy. But it doesnt quite make sense. If all men are logical then they shouldnt be shooting at all. If A shoot C, B will shoot A, and B will surely win (same thing for B). If A and B shoot each other then C surely will win. So yeah if they all think then one way or another who ever fire first will get killed so no one should fire at all.
Good job, Racers.
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Detour-
Wiki Search
or
Illusion Search
In wiki search, try to find my wikipage that tells you where to go for the PITSTOP.
In Illusion Search, look at the comments for some of the illusion teasers.
PM me also "Teaser Comment" to log your standings.
This was difficult for me (not a problem, though). It was fun and I rated it TOPS. Thanks for posting and thanks for visiting some of my teasers.
three gunmen has chances of shooting themselves
The biggest problem I have with this is that there is no mention that the men know each others strengths and weaknesses. However, since the teaser implies there is only one correct answer, you have to fill in some blanks to make that true. When you do, you come to the logical conclusion (as any good Vulcan would) that Cam is left standing.
it never says that they were shooting each other.
I was thinking along the lines of Bob surviving. My logic was that having a stronger gun may have recoiled enough to dislodge him from his horse causing whoever was firing to miss.
But, the other guy has a 100% chance if he aims at Bob right? Well in this scenario I see no difference between a strong and weak gun as evidenced by the answer; both men die. Why else mention a strong gun??
Enjoyed it though!
But, the other guy has a 100% chance if he aims at Bob right? Well in this scenario I see no difference between a strong and weak gun as evidenced by the answer; both men die. Why else mention a strong gun??
Enjoyed it though!
To add confusion to that fact.
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