(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
