12/25 ( ) = 11/50
( ) = 11/50 * 25/12 = 275 / 600 =
11/24
This can also be found by "formula"
Let A = Prob of second ball green
B = First ball is green = 12/25
P (A and B) = P (Both balls are green) = 11/50
P ( A given B ) = P( A and B) / P (B)
So we have :
P ( A given B) = ( 11/50) / (12/25) = (11/50) (25/12) = 11/24
