Dear rico7,
As a statistician I hate to tell you this but your website http://www.geocities.com/7life/deal.html is complete garbage.

Take this scenario from your site:

10p £15,000
£50 £50,000
£250,000

The odds of taking out the £250,000 in the next 3 boxes = 3/5 or 60%
The odds of taking out the £250,000 and the £50,000 in the next 3 boxes = 3/10 or 30%
The odds of taking out the £250,000, the £50,000 and the £15,000 in the next 3 boxes = 1/10 or 10%
The odds of taking out the £15,000, the £50, and the 10p in the next 3 boxes = 1/10 or 10%

The maths iis complete rubbish because the choice of all five boxes in not available to the player as one box is their own and therefore 'unpickable'. The maths is more complex than you make it out to be! Do your research beforehand pal!

with a name like that you are so much a troll ignore it Rich your site is fab

I don't know much about stats or maths, but is this guy making a fair point or not? If he isn't and is just being rude for no reason, then he is a troll for sure! (I think the name gives it away!)

The maths is correct.

Rico is correct because it's totally irrelevant that you can't pick your own box.

To explain: if you have 5 boxes remaining and you know that the £250,000 is in one of them, there's an equal 1 in 5 chance that it's in any particular box, whether you can choose it or not.

If you have 4 boxes left to choose from, there's a 20% chance that the £250k is in your own box and therefore an 80% chance that it's one of those remaining 4. You have to pick 3 of those 4 so there's a 75% chance you'll pick it *if it's there* (which we've just shown is an 80% chance). Therefore the total chance that you'll pick the 250k from the last 4 boxes is 0.8 x 0.75. Guess what? 0.8 x 0.75 is 0.60, ie a 60% or 3 in 5 chance, which is exactly what Rico said in the first place.

To complete the calculation, the chance that it's in your own box is obviously 20%, or 1 in 5. The odds that it's in the box you *don't* pick from the last 4 are 80% x 25% (because it'a an 80% chance the box is in those 4 and there's a 25% (or 1 in 4) chance you *won't* pick it if it is). So 0.80 * 0.25 is 0.2 or 20% probability.

So when you add the chance that it's in the 3 you pick PLUS the chance it's in the one you don't PLUS the chance it's in your own box you get 60% + 20% + 20% = 100%. Probabilities always have to add up to 100% of course because the box has to be *somewhere*.

In a nutshell, dond_is_dire is talking rubbish. It's a bit of a give-away that he thinks Rico's wrong but doesn't bother to explain how it *should* work in his opinion. Come on then dond_is_dire, put your money where your mouth is and explain exactly why you think Rico is wrong. Don't just make a vague claim - prove it mathematically. Oh that's right, you can't prove something that isn't true!

Sorry to go into math-nerd mode there but it had to be done.

Well it just goes to show someone is uneccesarily trying to cause trouble again.

yes little troll please go back down your hole
you are obviously bored so sign off the dole

Thanks Suezan, and thanks to Muttleee and everyone else for your support!