In jar A there are 3 white balls and 2 green ones, in jar B there is one white ball and three green ones. A jar is randomly picked, what is the probability of picking up a white ball out of jar A?  Choose the correct choice from the following answers.
A) 2/5
B) 3/5.
C) 3/10
D) 3/4
E) 2/3
Prob of picking jar A = 1/2   Prob of picking a white ball from jar A = 3/5   Prob of picking up a white ball out of jar A = 1/2*3/5 = 3/10   Hence, answer will be 3/10.
<result>C</result>
In jar A there are 3 white balls and 2 green ones, in jar B there is one white ball and three green ones. A jar is randomly picked, what is the probability of picking up a white ball out of jar A?