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.

Explanation

To solve the problem step by step, we will first summarize the information given and then calculate the required probabilities.

### Given:
- Number of red balls = 5
- Number of white balls = 8
- Number of black balls = 7

### Total number of balls:
...