Question

United Medicine, Inc., claims that a drug, Viro, significantly relieves the symptoms of a certain viral infection for 90 percent of all patients. Suppose that this drug is given to 15 randomly selected patients who have been diagnosed with the viral infection. (a) Let x equal the number of the 15 randomly selected patients whose symptoms are significantly relieved. What distribution describes the random variable x ? (B) Assuming that the company's claim is correct, find P(x ≤ 8). (c) Suppose that of the 15 randomly selected patients, 8 have had their symptoms significantly relieved by Viro. Based on the probability in part b, would you believe the claim of United Medicine, Inc.?

Answer 1

Here Success = Symptoms are relieved

P (Sucess) = 0.9

X = Number o patients relived by drug

Hence,

The claim in part c is not believable since probability of having 8 or below 8 is 0.0003

that means in a long run only 3 of 10000 cases is such that where the claim is less or equal to 8.

****The probability is calculated by pbinom(8,15,0.9) in R software.