CONDITIONAL PROBABILITY ASSISTANCE?

Question

asked Oct 22, 2019 173k views

1 Answer

Sandesh Sapkota · Answer 1 · 2019-10-27T23:01:17+0000

WE need to find the probability (
(Junior)/(girl) )

We know Probability (
(A)/(B) ) =
(P(A and B))/(P(B))

P (
(Junior)/(Girl) ) =
(P(Junior and girl))/(P(girl))

First we find P(Girl)

From the table we can see that we have 18 girls out of (12+18=30) students

So P(Girl) =
(18)/(30)

Now we find the intersection of Junior and Girl

WE look at the Junior row and girls column that is 3

{P(Junior ∩ Girl) =
(3)/(30)

P (
(Junior)/(Girl) ) =
(P(Junior and girl))/(P(girl))

P (
(Junior)/(Girl) ) =
((3)/(30))/((18)/(30))

=
(3)/(18) = (1)/(6)