Monday, September 24, 2007

Loaded Revolver Puzzle

Loaded Revolver Puzzle
Henry has been caught stealing cattle, and is brought into town for justice. The judge is his ex-wife Gretchen, who wants to show him some sympathy, but the law clearly calls for two shots to be taken at Henry from close range.
To make things a little better for Henry, Gretchen tells him she will place two bullets into a six-chambered revolver in successive order. She will spin the chamber, close it, and take one shot. If Henry is still alive, she will then either take another shot, or spin the chamber again before shooting.
Henry is a bit incredulous that his own ex-wife would carry out the punishment, and a bit sad that she was always such a rule follower. He steels himself as Gretchen loads the chambers, spins the revolver, and pulls the trigger. Whew! It was blank. Then Gretchen asks, "Do you want me to pull the trigger again, or should I spin the chamber a second time before pulling the trigger?"

What should Henry choose?


  1. Henry should choose pull the trigger without spinning the chamber as the probability to have bullet in the case of without spinning is 1/4 (because the bullets are in consecutive chambers suppose A and B. first is A and second is B. so, we can't go to B. and we can't be at it's present position again. So, 1/4 is the probability) and in case of spinning again the probability is 1/3 (it's simple). as according to our 5th class maths books 1/3 > 1/4 and it will make the chances of bullet more. So, henry should chose without spinning the triggers. Good luck henry. magar yaar yeh cattle churaane pe maut ki saza ... yeh kahan ka kanoon hai ...

  2. may be i am wrong but
    isnt probablity that after first shot bullet in next hole is 1/2 and if they spin it is 1/6


Subscribe via email

Enter your email address:

Delivered by FeedBurner