Problem 5.51 Binomial Distribution : A consumer advocate claims that 80 percent of cable television subscribers are not satisfied with their cable...
View the step-by-step solution to:

Question

Problem 5.51   Binomial Distribution: A consumer advocate claims that

80 percent of cable television subscribers are not satisfied with their cable service. In an attempt to justify this claim, a randomly selected sample of cable subscribers will be polled on this issue.

 

a           Suppose that the advocate's claim is true, and suppose that a random sample of five cable subscribers is selected. Assuming independence, use an appropriate formula to compute the probability that four or more subscribers in the sample are not satisfied with their service.

show your work to calculate P(x ³ 4) = 1 - P(x £ 3):


b           Suppose that the advocate's claim is true, and suppose that a random sample of 25 cable subscribers is selected. Assuming independence, find:

(1)        The probability that 15 or fewer subscribers in the sample are not satisfied with their

service.


(2)        The probability that more than 20 subscribers in the sample are not satisfied with their

service. show your work to calculate P(x > 20) = 1 - P(x £ 20) to get your final answer:




(3)        The probability that between 20 and 24 (inclusive) subscribers in the sample are not

satisfied with their service.

(A) Minitab instructions: Go to Calc > select Probability Distributions > select Binomial > select Cumulative probability > Number of Trials insert 25 > Event Probability insert ".8" > Input Constant insert "19." Click OK.

(B) Minitab instructions: Go to Calc > select Probability Distributions > select Binomial > select Cumulative probability > Number of Trials insert 25 > Event Probability insert ".8" > Input Constant insert "24." Click OK.

show your work to calculate P(20 £ x £ 24) = P(x £ 24) - P(x £ 19) to get your final answer:

 

  

(4)        The probability that exactly 24 subscribers in the sample are not satisfied with their service.

 

c           Suppose that when we survey 25 randomly selected cable television subscribers, we find that 15 are actually not satisfied with their service. Using a probability you found in this exercise as the basis for your answer, do you believe the consumer advocate's claim?

Top Answer

a. 0.73728 0.01733186954... View the full answer

Sign up to view the full answer

Why Join Course Hero?

Course Hero has all the homework and study help you need to succeed! We’ve got course-specific notes, study guides, and practice tests along with expert tutors.

  • -

    Study Documents

    Find the best study resources around, tagged to your specific courses. Share your own to gain free Course Hero access.

    Browse Documents
  • -

    Question & Answers

    Get one-on-one homework help from our expert tutors—available online 24/7. Ask your own questions or browse existing Q&A threads. Satisfaction guaranteed!

    Ask a Question