Historical data indicates that only 20% of cable customers are willing to switch companies.If a binomial process is assumed,then in a sample of 20 cable customers,what is the probability that exactly 2 customers would be willing to switch their cable?
A)0.1
B)0.04
C)0.137
D)0.206
E)0.794

Question

Quizplus · Accepted Answer

The probability of a customer switching is 0.2 (20% expressed as decimal). Thus, the probability of exactly 2 customers switching in a sample of 20 is:

P(2 customers switching out of 20) = (20 choose 2) * (0.2)^2 * (0.8)^18
= (190) * (0.04) * (0.107) 
= 0.137

Therefore, the answer is C.

Historical Data Indicates That Only 20% of Cable Customers Are