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**jagxj12** · 09-16-2012, 07:12 PM

If by the end of day 1, you are 1-1, then your chances of getting 2 of the next three are 2/3, 66% (if matches are at random)

That is clearly not so - both teams have 50% chance of winning.

Mathematical formula for determining probability of event happening is given by this formula:

Pr = (n/k)pkqn-k where n = times played (3 in our case), k = wins needed (2), p = probability of success (random so 0.5), q = probability of failure (also 0.5).

This will give 0.375, however that is a probability of winning exactly 2 matches. Since 3 out of 3 is also good for our cause you'll have to add the probability of that (0.125) giving the final and rather obvious answer of 50% chance.

You can also use this webpage (binomial trials calculator) to do all kinds of more complex probability calculations.

09-16-2012, 07:12 PM	#6
jagxj12 Join Date Oct 2005 Posts 609 Senior Member	If by the end of day 1, you are 1-1, then your chances of getting 2 of the next three are 2/3, 66% (if matches are at random) That is clearly not so - both teams have 50% chance of winning. Mathematical formula for determining probability of event happening is given by this formula: Pr = (n/k)pkqn-k where n = times played (3 in our case), k = wins needed (2), p = probability of success (random so 0.5), q = probability of failure (also 0.5). This will give 0.375, however that is a probability of winning exactly 2 matches. Since 3 out of 3 is also good for our cause you'll have to add the probability of that (0.125) giving the final and rather obvious answer of 50% chance. You can also use this webpage (binomial trials calculator) to do all kinds of more complex probability calculations.
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