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Permutations/Combinations Stars indicate particularly
interesting answers or good places to begin browsing. -
Probabilities of Picking Colored Balls out of an Urn
[03/13/2006] An urn contains 8 white, 6 blue, and 9 red balls.
How many ways can 6 balls be selected to meet various given
conditons? - Probability and Permutations [09/12/1999] A
permutation f is a 1-1 mapping of the first n positive integers
onto themselves. What is the probability that the permutation
has the property that f(i) = i for at least one value of i, i
between 1 and n inclusive? - Probability of Duplicate Pairs
[05/13/2003] Find the probability of getting at least 20
duplicate addresses when drawing a sample of 30,000 at random
from UK households (estimate 21,000,000) where there is
replacement every time a selection is made. - Probability of
Never Having a Losing Record [04/07/2001] Suppose a football
team plays 8 games, and the chance of winning any particular
game is 50%. What is the prob