Re: A Microsoft Interview Question (aka basic Bayes\' Theorem)
Guys, at the time the first player pulls the trigger, there are SIX possible states for 2 bullets in the 6-gun:
2 Bullets adjacent in 6 possible chambers:
1&2
2&3
3&4
4&5
5&6
6&1 (whoops)
OK, six.
Let's assume chamber #1 was the chamber that clicked for player #1.... with no bullet inside.
That eliminates the first possible state (1&2) and the last possible state (6&1) from consideration, leaving 4 possible states (of initially 6 possible) remaining for the 2nd player to deal with.
Only one of them can kill you now (2&3) so you are looking at 1 chance out of 4 that you are going to die if you do not spin.
If you choose to instead spin the 2 bullets in the 6 chambers, there is a 2/6 = 1 out of 3 chance you will get a headache.
Don't spin and you have a 1 in 4 chance of a bullet.
Spin and you have a 1 in 3 chance of a bullet.
Don't spin.
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