1. You can order a new model of an electronic notebook in one of five colors. Th
ID: 3340996 • Letter: 1
Question
1. You can order a new model of an electronic notebook in one of five colors. The notebook also comes loaded with one of four different games. How many different combinations of colors and games are possible? If you were to order three different notebooks without stating preference on color or games, what is the probability that they are identical? Assume that the color and game on one notebook is independent of any others.
2. Firms are increasingly asking applicants to submit to drug tests. Suppose that drug tests can identify a drug user 98% of the time. However, 1% of the time the test indicates a positive result although the applicant is not a drug user. If 10% of all applicants are drug users, what is the probability that a person who has tested positive for drug use is not really a drug user?
Explanation / Answer
Question 1:
The total number of different combinations of colors and games are possible here is computed as:
= Total number of distinct colours * total number of different games = 5*4 = 20
Therefore there are a total of 20 combinations possible here.
Now the probability that the three notebooks ordered are all identical is computed as:
= Total number of distinct notebooks * Probability of getting identical notebook each of the three times
= 20*(1/20)*(1/20)*(1/20)
= 1/400
= 0.0025
Therefore 0.0025 is the required probability here.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.