TicTac wrote:
I'll try and work out some odds:
If you do 22 shows, the chances of having every value, (or every box number) are:
(1/1) x (21/22) x (20/22) x (19/22) x (18/22) ....... x (1/22)
Which can be shortened to (21!/22^21)
Which equals 3.29 x 10^-9 or 1 in 303,761,260...
I'm trying to work out what happens at 23 boxes and so on and I think its to do with getting 22 more chances at the combination. e.g. 23 combinations of aaaaaaaaaabaaaaaaaaaaa where a is a different value and b is the same value.
So then it gets complicated with 24 and 2 'Bs' as theres even more combinations. If I understand my pascals triangle correctly thats 276 combinations.
So for 30 boxes, we have 22 'similar' values, and 8 'different' values so the amount of combinations is 58,529,925. This means the odds for having all 22 different values or box numbers in 30 games is:
This means the odds of having all 22 values in 30 games are about 1/5.
*beep* those odds are too short lol. I've mucked up somewhere...
I only did this coz I was bored of some current maths I'm doing... so its probably not understandable anyway ^^
I think I'm vaguely on track, and I'm sure MisterAl will probably be here soon...
When I was looking at this topic yesterday, my initial idea for calculating this probability was pretty much the same as what you've done. However, it's not right because it assumes that only 1 of the combinations (of which there are 58,529,925 in your example) will give the 22 different values, when it could be that many of the combinations do.