Find the probability of no more than 2 successes in 5 trials of a binomial experiment in which the probability of success in any one trial is 18%
Although I am not so great on these problems, I have found a very useful article that you can use to solve this problem.
Here is the link:
https://www.varsitytutors.com/hotmath/hotmath_help/topics/binomial-probability
This is a binomial probability problem. The relevant formula is: prob = nCr·pr·qn - r
where: n = total number of trials n = 5
r = number of successes r = 0, 1, 2
p = probability of success p = 0.18
q = probability of failure q = (1.00 - 0.18) = 0.82
For this problem, to find the total probability, we need to find the probability for 0 successes, then 1 success, and
finally 2 successes, and add them together.
Total probability = 5C0·(0.18)0·(0.82)5 + 5C1·(0.18)1·(0.82)4 + 5C2·(0.18)2·(0.82)4
Now, it's between you and your calculator!