You can put this solution on YOUR website! We us the binomial probability(P) formula
P(r success in n trials) = nCr * p^r * q^(n−r)
Where,
p = the probability of success and
q = the probability of failure (or complement of the event)
n = Total number of trials
r = number of specific events we want to obtain
nCr represents selection of r events from n, it can be written as: nCr = n! / (r!*(n−r)!)
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1) P(r > or = 2) = P(2) + P(3) + .... + P(n)
2) P(r < or = 3) = P(0) + P(1) + P(2) + P(3)
3) P(r = 4) = P(4)
