Answer:
(a) The probability of an adult using non-prescription antidepressants given that he visited the therapist is 0.78.
(b) The probability of an adult visited the therapist given that he was using non-prescription antidepressants is 0.46.
Step-by-step explanation:
Conditional probability of an event <em>X</em> given that another event <em>Y</em> has already occurred is:
Let <em>A</em> = an adult visited the therapist and <em>B</em> = an used non-prescription antidepressants.
Given:
P (A) = 0.27
P (B) = 0.46
P (A ∩ B) = 0.21
(a)
Compute the probability that a randomly selected adult who visited a therapist during the past year also used non-prescription antidepressants as follows:
Thus, the probability of an adult using non-prescription antidepressants given that he visited the therapist is 0.78.
(b)
Compute the probability that a randomly selected adult visited a therapist during the past year, given that he or she used non-prescription antidepressants as follows:
Thus, the probability of an adult visited the therapist given that he was using non-prescription antidepressants is 0.46.