The probability that a patient will NOT be given a placebo would be equal to 7/17.
How to calculate the probability of an event?
Suppose that there are finite elementary events in the sample space of the considered experiment, and all are equally likely.
Then, suppose we want to find the probability of an event E.
Then, its probability is given as
[tex]P(E) = \dfrac{\text{Number of favorable cases}}{\text{Number of total cases}} = \dfrac{n(E)}{n(S)}[/tex]
where favorable cases are those elementary events that belong to E, and total cases are the size of the sample space.
A drug trial is testing the effectiveness of two drugs.
If 50 patients are given Drug A,
20 patients are given Drug B,
100 patients are given a placebo.
So, The total number of patients that are given drug and placebro
= 20 + 50 + 100
= 170.
Then you'd take how many patients are taking a real drug, which is represented by
20 + 50 = 70.
So, the probability of a patient NOT getting a placebo
= 70/170
= 7/17.
The answer is D 7/17.
Learn more about probability here:
brainly.com/question/1210781
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