Thus, the probability distribution of number of successes in an experiment consisting
of n Bernoulli trials may be obtained by the binomial expansion of (q + p)n Hence, this
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PROBABILITY      575
distribution of number of successes X can be written as
X
0
1
2 x n
P(X)
nC0 qn
nC1 qn–1p1
nC2 qn–2p2
nCx qn–xpx
nCn pn
The above probability distribution is known as binomial distribution with parameters
n and p, because for given values of n and p, we can find the complete probability
distribution