Question

A bag contains 4 red, 5 black and 6 white balls. One ball is drawn from the bag at random. Find the probability that the ball drawn is: (i) white (ii) red (iii) not black (iv) red or white Select the correct answer from above options

Answer 1

(i) White Total numbers of red balls = 4 Number of black balls = 5 Number of white balls = 6 Total number of balls = 4 + 5 + 6 = 15 Probability of getting a white ball is = Total number of white balls/Total number of balls = 6/15 = 2/5 ∴ Probability of getting a white ball is 2/5 (ii) Red Total numbers of red balls = 4 Number of black balls = 5 Number of white balls = 6 Total number of balls = 4 + 5 + 6 = 15 Probability of getting a red ball is = Total number of red balls/Total number of balls = 4/15 ∴ Probability of getting a white ball is 4/15 (iii) Not black Total numbers of red balls = 4 Number of black balls = 5 Number of white balls = 6 Total number of balls = 4 + 5 + 6 = 15 Number of non-black balls = 4 + 6 = 10 Probability of getting a non-black ball is = Total number of non-black balls/Total number of balls = 10/15 = 2/3 ∴ Probability of getting a non-black ball is 2/3 (iv) Red or white Total numbers of red balls = 4 Number of black balls = 5 Number of white balls = 6 Total number of balls = 4 + 5 + 6 = 15 Number of red and white balls = 4 + 6 = 10 Probability of getting a red or white ball is = Total number of red or white balls/Total number of balls = 10/15 = 2/3 ∴ Probability of getting a red or white ball is 2/3