Question: which one of the following is a binomial random variable?
Answer: It can be as low as 0, if all the trials end up in failure, or as high as n, if all n trials end in success. The random variable X that represents the number of successes in those n trials is called a binomial random variable, and is determined by the values of n and p. We say, “X is binomial with n = … and p = …”