Question

A bag contains 5 red,8 white ,7 black balls .a ball is drawn at random from bag find the probability that the ball drawn is 1] red or white 2) not black 3) neither white nor black

Answer 1

1) P (red or white ball) = (5+8)/20 = 13/20

2) P(not black) = 13/20

3) P(neither white nor black) = 5/13

Answer 2

1) P (red or white)=no.of red+ white/total no. Of balls   =13/20 2) P (not black) = 1-P (black)  =1-7/20   =13/20 3) P (neither white nor black)= P (red)    =5/20