Two balls are selected at random from a bag with three red balls and two yellow balls. Find…
a) probability that the first ball is red
3/5 . 2/4 + 3/5 . 2/4 = 3/5
b) probability that the second ball is red
2/5 . 3/4 + 3/5 . 2/4 = 3/5
c) probability that both are red
(3c2)/(5c2) = 3/10
d) probability that the second ball is red, given that the first ball is red
P(A|B) = P(AB)/P(B) = (3/10)/(3/5) = 1/2
Are my workings correct?