Question

1. The statistics of campus interviews show that for every 10 interviews 4 job offers are made. Out of 66 interviews, what is the probability that at least 30 offers would be made? (Use TI-84, Silver Edition.)

2. Refer to Question 1. What would be the expected number of job offers made?

3. Refer to Question 1. What would be the standard deviation σ of the number of job offers made?

4. Assume that 20 percent of the babies get fever after immunization shoots. If 130 babies are immunized in a clinic, what is the probability that at most 30 will get fever?

5. Refer to Question 4. What is the expected number of babies that would get fever?

6. Refer to Question 4. What would be the standard deviation σ ?

7. It is assumed by the coach that a swimmer can finish an event within target time 45 percent times during practice. Suppose the swimmer swims 80 times. What is the probability that he/she will finish within the target time at least 40 times?

8. Refer to Question 8. What is the expected number E(X) of times that he/she will finish within target time?

9. Refer to Question 8. What is the standard deviation σ of the number of times X that he/she will finish within target time?

10. It was reported, that 20 percent of the population in a region were infected by AIDS-HIV. A sample of 200 people from this region were examined for AIDS-HIV. What was the expected number of infected people?

Answer 1