Answer to Question #197036 in Statistics and Probability for Md.Mehedi Hasan

Question

At Covington High School, 20% of sixth-form mathematics students retake their C1 module. There are 15 students in Mr Smither’s class; find the probability that precisely four of them retake this module

Answer 1

$p=0.2,n=15$

Given Distribution is a binomial distribution.

X$\sim$ B(15,0.2)

Probability that precisely four of them retake this module

$P(X=4)=^{15}C_4 (0.2)^4(1-0.2)^{ 11}$

$= 1365\times 0.0016\times 0.085\\=0.1876$