If x has a 0.0002% chance per event, how many events until x has a 95% chance?

[Ronon]

Q. If x has a 0.0002% chance per event, how many events until x has a 95% chance?

How would I work out something like this? Are there any calculators that would figure this sort of thing out for me? This is for my curiosity, I've been out of school for years

 

[Deleted member 4993]

How would I work out something like this? Are there any calculators that would figure this sort of thing out for me? This is for my curiosity, I've been out of school for years

First time 'x' does not happen = (1-0.000002)

2nd time 'x' does not happen = (1-0.000002)²

3rd time 'x' does not happen = (1-0.000002)³

Now continue....

 

[sensational]

First time 'x' does not happen = (1-0.000002)

2nd time 'x' does not happen = (1-0.000002)²

3rd time 'x' does not happen = (1-0.000002)³

Now continue....

I think you just