Hi
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re: BINOMIAL Probability Distribution
Note: The probability of x successes in n trials is:
P = nCx*where p and q are the probabilities of success and failure respectively.
In this case p =.8 and q = .2 and n = 4
nCx =
P(0) = (.2)^4 = .0016
P(1) = 4(.8)^1(.2)^3 = 0.0256
P(2) = 6(.8)^2(.2)^2= 0.1536
P(3) = 4(.8)^3(.2)^1 = 0.4096
P(4) = (.8)^4 = 0.4096
Mean = np = 4*.8
Variance = npq = 4*.8*.2
P(at least one) = 1- P(0)
P(more than one) = 1 - P0) - P(1)