Answer:
P(B)= 17/20
Step-by-step explanation:
Hello!
The audience of the magic show is conformed by a total of 120 people, 52 of which are female and 68 are men.
Within the audience there is a school class of 37, of these students, 17 are female and 20 are male.
If a random member of the audience is selected as a volunteer:
Let "A" represent the event that "the selected volunteer is a student of the class"
And "B" the event that "the selected student is female"
You have to calculate the probability of the selected volunteer being female, given that it is a member of the school class.
Symbolically:
P(B|A)
Using the formula of conditional probabilities you can calculate it as:
P(A∩B)= =
As you can see the probability of the event "The volunteer is female given that it was a student of the school class" means that you already know the selected volunteer was a student and only needed to calculate the probability of that student being female.
P(B)= 17/20
I hope this helps!