You are playing Russian roulette: will you spin or not spin. Conditions given below.?

Question

There are 6 chambers in the revolver. You are told that there are two bullets in the revolver in ADJACENT chambers. The revolver spins in one direction only (either clockwise or counter-clockwise NOT both). You pulled the trigger once and obviously you didn't die (otherwise you wouldn't be answering this question). So you get another chance (2 bullets, 2 shots, only fair). Do you spin the revolver again before pulling the trigger or do you simply pull the trigger. Justify your decision.

Well dacihak, I gave a pretty precise scenario. I can't help if people choose to ignore the conditions I set. blahb31 is correct. She also drew the picture (thus reducing my agony of explaining it in words later on).

Puppy Zwolle, you are correct too, and you are humorous. :))

"talking my life.. any change is dramatic.." funny!

Answer 1

If you don't spin, then there are five left. Now since you said that the two bullets are next to each other and you didn't get shot the first time, then they both count as the same bullet, so that there are four possibilities left. So that means the you have a 1 in 4 chance of getting shot. You can also think of it this way: say you have this situation.

1 2 3 4 5 6
X X X B B X

so that there is a bullet in positions 4 and 5. Since you shot once and got a blank, then that means you either were in the 1, 2, 3, or 6 position. Out of those, only one (position 3) has a bullet the next time. So the chance of getting shot is 1 in 4.

If you do spin, then you have a 2 in 6 chance of getting shot, since then you can consider that a repeat of the previous round.

Since 1/4 is smaller than 2/6, I would go with not spinning.

********************************************************************

This is a different result than if we couldn't assume whether the bullets are together or not. Not spinning in that case would lead to a 2 in 5 chance of getting shot; spinning would lead to a 2 in 6 chance of getting shot. In that case, spinning would be better.

This is an interesting question. I'll need to keep it in mind for my students one day!

Answer 2

There a 6 chambers and a series of 2 in them.
When I pull the first time I have a 2 in 6 (1 in 3) chance of killing me.

As I didn't chances dramatically change. We are talking my life here, any change is dramatically. The next one can be an empty chamber or the first of the series of 2 and that I would not like. There are 5 slots left where a series of 2 fits in. That's 4 possible combinations.

1) bxx000
2) b0xx00
3) b00xx0
4) b000xx
b=bang, x=bullet, 0=empty.

The chance is now 1 in 4 I will shoot myself. Spinning would 'reset' chances to 1 in 3.

If I were to play this 'game' I'd theoretically would be better of pulling the trigger.

I want to lose life as a result of using it not abusing it. :)

Answer 3

The only random event is the spin of the chamber.

When you first spin it, there is a 3/6 or 1/2 chance that you will land on the first of two empty chambers. This probability cannot change so after your first shot there is a 1/2 chance that the second shot will be blank.

However, each spin has a 4/6 or 2/3 chance of finding an empty cylinder.

Spin again.

Answer 4

1) There are four possible positions where pulling the trigger the first time does not kill you. Since you survived, there are three of these remaining.
2) Of the these three, if you do not spin again, only one will result in your death during the next trigger pull. Thus, there is 1 in 3 chance that you will go to the promised land.
3) If you do spin again, its like starting all over. There are four positions out of six that you can land on safely, or a 2/3 chance of surviving a trigger pull.

So, I would recommend that you spin again before pulling the trigger, unless you are a radical Muslim, in which case I hope you enjoy the 72 virgins.

Answer 5

As someone said, this is a very good question. I think that the person should simply pull the trigger again. The worst situation is that prior to pulling the trigger for the first time, the first of the two consecutive bullets will be next in the firing chamber. There is only a one in six chance of this happening. If however, he decides to spin the chamber, we have a two in six (or one in three) chance that one of the bullets will line up with the firing pin.

So keep your cool...pull the trigger again!

Answer 6

Okay here's how it goes, we have 6 chambers, 2 loaded and 4 empty. When you spin, the probability that the chamer you are about to fire is empty is 4/6 = 2/3 (about 66.7%)
As you said above, you shoot and it turns out to be empty, so now we examine the senario, you have 5 chambers, 3 empty and 2 loaded. So the probabilty that hte current chamber is empty and that you will survive the 2nd shot is now 3/5 (60%). If you spin again the you go back to 6 chambers, 4 empty, 2 loaded and have hte same 2/3 (66.7%), so in terms of probablity you should spin.
Just FYI, when playin Russian Roulette, you only spin the revolver once.

Answer 7

Your gonna wanna spin it because if you take the next chamber there is a 2 in 5 chance you will be shot dead. Whereas if you spin it your back to a 2 in 6 chance.

Answer 8

If you do spin, chances there is no bullet = 4/6 = 2/3

If you do not, then one empty has gone

The next may be loaded or may not

So chance = P(not loaded) = 3/6 = 1/2

Better spin.

Answer 9

blahb is right. Don't listen to those other people.

If the first chamber is blank, there's only going to be 1 scenario where the bullet is next. Every one keeps forgetting the bullets are adjacent

Answer 10

just pull
same odds as if spinning.