The calculator below gives the probability that there is at least one success when an event is repeated ‘n’ times. Let ‘n’ denote the number of Bernoulli trials and let ‘p’ denote the probability of success. Then the probability of at least one success is given by the formula, \text{Probability} = 1- (1-p)^n
Example:
Suppose that a coin is tossed 4 times and we wish to find the probability that we get heads (success) at least once. Here, n=4 and p=0.5, and hence the probability can be calculated as, \text{Probability} = 1- (1-p)^n = 1- (1-0.5)^4 = 0.9375
Simply input the values of p and n into the calculator below to obtain the probability of at least one success.
p (probability of success in a given trial)
n (number of trials)
P(at least one success) = 1 – P(failure in a given trial)n
P(at least one success) = 1 – (0.96)3
P(at least one success): 0.11526