A bag contains 3 red balls, 5 black balls, and 4 white balls. A ball is drawn at random from the bag. What is the probability of not getting a black ball?
712
Number of balls = 3+5+4 = 12
Number of balls that are not black
= Number of red balls + Number of white balls
= 3 + 4 = 7
∴ Required Probability = 712.