CT6-Math109: Probability Subjects were given the cholesterol-treating drug Lipit
ID: 3206450 • Letter: C
Question
CT6-Math109: Probability
Subjects were given the cholesterol-treating drug Lipitactim to test whether it contributed to headaches. The table below shows subjects who were given the drug and subjects who were given a placebo and whether any in each of these groups experienced headaches. Use the table below to answer the following question.
Treatment
Lipitactim
Placebo
Headache
15
65
No Headache
17
3
Answer the following questions please showing how you came up with the answer:
1). If one subject was randomly selected, find the probability that he or she had a headache, given the fact that they took Lipitactim.
2). If the probability of an event is 60%, what are the odds?
3). By investing in a particular stock, a person can take a profit in a given year of $4000 with a probability of 0.3 or take a loss of $1000 with a probability of 0.7. What is the investor's expected gain on the stock
Treatment
Lipitactim
Placebo
Headache
15
65
No Headache
17
3
Explanation / Answer
Total number of subjects are 15 + 65 + 17 + 3 = 100
(1)
there are total 17+15 = 32 subjects who took Lipitactim.
Probability that subject had a headache = 15/32 = 0.4688
(2)
If the probability of an event is 60%, what are the odds?
Favorable outcomes = 60
unfavorable outcomes = 40
odds are expressed as the ratio of favorable outcomes to unfavorable outcomes
here odds are 60:40 = 3:2
(3)
Expected gain = 4000 * 0.3 - 1000 * 0.7 = 500