Question 635427
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Hi,
Suppose that an experiment is repeated four times. 
A certain event has probability 1/10 in a single repetition of the experiment.
P = nCx* {{{p^x*q^(n-x)}}} where p and q are the probabilities of success and failure respectively. 
In this case p = .1 and q = .9 ,   n = 4   
 P(x = 0) = {{{(.9)^4}}}       | nCx = {{{n!/(x!(n-x)!)= 4C0 = 1}}}