Respuesta :
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:
[tex]P(B|A)= \frac{P(AnB)}{P(A)}[/tex]
P(A∩B)= [tex]P(A)*P(B)= (\frac{37}{120} )*(\frac{17}{20} )[/tex]= [tex]\frac{629}{2400}= 0.26[/tex]
[tex]P(A)= \frac{37}{120} = 0.308[/tex]
[tex]P(B|A)= \frac{P(AnB)}{P(A)}= \frac{629/2400}{37/120} = \frac{17}{20} = 0.85[/tex]
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!
Answer:
alright, this is what I did.
p(a)=37/120
p(b)=17/37
p(anb)=(37/120)(17/37)=17/120
p(anb)/p(a)=17/120 divided by 37/120
=17/37
The probability of a person being picked being from the class and a female is 17/37.