Question

A bag contains 5 red, 8 white and 7 black balls. A ball is drawn at random from the bag. Find the probability that the drawn ball is (i) red or white (ii) not black (iii) neither white nor black.

Answer 1

Answer:

(1) 13/20

(2) 13/20

(3) 1/4

Answer 2

(i) 13/20 ; (ii) 13/20 ; (iii) 1/4

Step-by-step explanation:

A bag contains 5 red, 8 white and 7 black balls.

So total outcomes = 5 + 8 + 7 = 20

(i) Probability of red ball = 5/20

   Probability of white ball = 8/20

Probability that the drawn ball is red or white = 5/20 + 8/20 = 13/20

(ii) Probability of black ball = 7/20

  Probability of not black ball = 1-7/20 = 13/20

(iii) Probability of neither white nor black = 1 - (8/20 + 7/20) = 1 - 15/20 = 5/20 = 1/4