Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

of people oblem I. Yesterday it was announced that the first-ever cold vaccine t

ID: 3061630 • Letter: O

Question

of people oblem I. Yesterday it was announced that the first-ever cold vaccine to be tested in a large number has failed, over all, to protect them from infection with the virus that causes the disease, according to the company that makes the vaccine, ColdVax. People in the trial were either injected with the vaccine or with placebo. Among the results published in the New York Times were the following summary of the nu people at the end of the three-year trial Vaccine Placebo TOTAL Infected with Cold Not infected with Cold TOTAL 3,139 3,330 1,581 1,679 4,720 5,009 What was the probability that a person in the trial was given the vaccine instead of the placebo? 3,139 3,330 3,139 5,009 3,330 5,009 191 d) b) c) 3,330 10. Of the people given the vaccine, what was the probability they were not infected with a cold at the end o the three-year trial? 3,139 3,330 3,139 5,009 3,330 5,009 3,330 11. Of th e people given the placebo, what was the probability they were not infected with a cold at the end of the three-year trial? 1,679 4,720 4,720 5,009 1,679 5,009 1,581 b) c) d) a) 1,679 Use Problem II to answer questions 12- 15 Problem II. The personnel director of DataBase SysCo classified job applicants as qualified or unqualified for the jobs they seek. The manager says that only 25% of the job applicants are qualified. Of those that are qualified, 20% list a bachelor's degree from a private, for-profit college as their highest level of educa Another 30% ofthe qualified applicant list a certificate from a trade school as their highest level of edu ation. The remaining 50% of the qualified applicants list CSU Fresno's BA in Business with an IS option as their highest level of education. The situation is different among the unqualified applicants in that 40% of them list a bachelor's degree from a private, for-profit school, 40% of the unqualified applicants list a certificate from a trade school, and only 20% of the unqualified applicants list CSU Fresno's BA in Business with an IS option as their highest level of education 12. According to the personnel director, what is the probability that a job applicant is unqualified? a) 75% b) 50% c) 27.5% d) 20% 13. What is the probability that a job applicant listed CSU Fresno's BA in Business with an IS option given you know that the applicant was qualified for the job? a) 75% c) 27.5% 14. What is the probability that any job applicant (whether qualified or unqualified for the job) listed CSU c) 27.5% 15. What is the probability that a job applicant is unqualified for the job given that that the job applicant c) 37.5% b) 50% d) 20% Fresno's BA in Business with an IS option? a) 75% b) 50% d) 20% listed a certificate from a trade school as their highest level of education? a) 80% b) 75% d) 30%

Explanation / Answer

9) Total number of subjects=5009

Number of subjects given vaccine=3330

Probability of being given a vaccine=3300/5009

Option (d) is the answer

10) Number of persons given vaccine=3300

Number of persons not infected with cold=3139

Probability=3139/3300

Option (b) is the answer

10) Number of persons given placebo=1679

Number of persons not infected with cold =1581

Probability= 1581/1679

Option (a) is the answer

11) Percentage of qualified applicants=25%

Percentage of unqualified applicants=75%

Option (a) is the answer

12) 50% of the qualified applicants list CSU Fresno's BA in Business with IS option

Probability=50%

Option (b) is the answer

13) 50% of the qualified applicants list CSU Fresno's BA in Business with IS option

20% of the unqualified applicants list CSU Fresno's BA in Business with IS option

Required probability=(0.5*0.25)+(0.2*0.75)=0.275=27.5%

Option (c) is the answer

15) Probability of qualified applicants listing certificate from trade school=.25*0.3=0.075

Probability of unqualified applicants listing certificate from trade school=.75*.4=0.3

Total probability of listing certificate from trade school=0.3+0.075=0.375

Probability that a job applicant is unqualified given that the applicant listed a certificate from trade school=0.3/0.375=0.8=80%

Option (a) is the answer