working out % chance?

[igetbadbeat]

[ QUOTE ]
assuming a 1 in 22 chance what is the chance of this event not happening after 5 times? 1 in 22 every time, not 1 in 21, 1 in 20 etc

[/ QUOTE ]

Your original wording is faulty. If you miss it the first time, your chances don't go up the 2nd time.

From the beginning when you have 3 chances, the odds of you not getting picked are 1-(1/22+1/22+1/22) or rather 19/22 is the odds you don't get it.

If you don't get picked the first time, your odds are 20/22 of not getting picked

and if you don't get picked the first two times, your odds are 21/22 not tog et picked @ that point.