Answer to Question #350260 in Statistics and Probability for Yohhailu85

Question

Suppose that 4% of all TVs made by A&B Company in 2000 are defective. If eight of 

these TVs are randomly selected from across the country and tested, what is the 

probability that exactly three of them are defective? Assume that each TV is made 

independently of the others.

Answer 1

Let $X=$ the number of defective selected TVs: $X\sim Bin(n, p).$

Given $n=8, p=0.04, q=1-p=0.96$

$$P(X=3)=\dbinom{8}{3}(0.04)^{3}(0.96)^{8-3}$$ $$\approx0.00292229575$$