If there are 18 people and each person has a 10 percent chance of getting a prize, what is the probability that 6 or more people get a prize? [closed]
If there are 18 people and each person has a 10 percent chance of getting a prize, what is the probability that 6 or more people getting a prize each?
Not sure how to approach this problem. Thanks in advance.
Solution 1:
Assuming that the events are independents, the probability is the following sum (see binomial distribution)
$$P = \sum_{r = 6}^{18} \binom{18}{ r} (0.10)^r (0.9)^{18 - r} = 1 - \sum_{r=0}^{5} \binom{18}{ r} (0.10)^r (0.9)^{18 - r} $$
It turns out that the probability is approximately $$0.00641515$$