Question

Box a contains 6 red and 4 blue balls ; box b contains 3 red and 7 blue balls . two balls are drawn at random from box a and placed in

b.now , a ball is drawn at random from box

b.find the probablity that it is a blue ball

Answer 1

b P(E)= favourable no. of outcomes/total no. of outcomes
P(blue ball)= 9/20