QUESTION 4 ( 8 marks)
A telemarketer is able make a sale on 28% of the phone calls hemakes. Assume that he makes 11 calls in an hour. Answer thefollowing questions, assuming a binomial probabilitydistribution:
Required:
- What is the probability that he will make exactly four sales inthe course of an hour? ( 3 marks)
- What is the probability that he will make at least three salesin the course of an hour? Hint: Use theapproach that requires the least calculation work! ( 5marks)
QUESTION 5 ( 8 marks)
Suppose 1.5% of the antennas on new Nokia cell phones aredefective. For a random sample of 240 antennas, answer thefollowing questions (assume a Poisson probabilitydistribution):
Required:
- Calculate the mean and standard deviation for the probabilitydistribution of the number of defective antennas in the randomsample. and What is the probability that exactly five of theantennas will be defective? ( 4 marks)
- What is the probability that less than three antennas will bedefective? ( 4 marks)
