Question

In a large population 40% votes for candidate A and 60% for candidate B. Suppose we select at random 10 people. What is the probability that in this group exactly 4 people will vote for A?

Answer 1

So, this is essentially the usage of binomial probability to solve the problem.

P(a) = .40

P(b) = .60

N=10

Pdf function = nCx*p^x*(1-p)^n-x

Subbing the values we get:

P(x=4 vote for A)= 10c4* (.4^4)*(.6^6)= 0.2508