Question

Hospital records show that of patients suffering from a certain disease 75% die of it. What is the probability that of 6 randomly selected patients, 4 will recover?

Answer 1

Let X be the binomial random variable denoting the number of patients. 

Let p be the probability that the patient will recover and q be the probability that patient will die. 

According to the problem, q = 75% = 0.75 and p = 25% = 0.25 and n = 6

Hence the probability that 4 patients will recover out of 6 patients is 0.03295