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Question
A bag contains 4 white balls, 5 red balls, 2 black balls and 4 green balls. A ball is drawn at random from the bag. Find the probability that it is red or white.
Solution
Total number of balls = 15
Number of balls which are either red or white = 4 + 5 = 9
∴ P(getting a ball which is red or white) = `"Number of favourable outcomes"/"Number of all possible outcomes" = 9/15`
Thus, the probability of getting a ball which is red or white is = 6
Thus, the probability of getting a ball which is red or white is `3/5`.
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