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Question
A bag contains six identical black balls. A child withdraws one ball from the bag without looking into it. What is the probability that he takes out:
- a white ball?
- a black ball?
Solution
There are six identical black balls.
∴ No. of possible outcomes = 6.
(i) A white ball
As there is no white ball in the bag.
∴ No. of favourable outcomes (of getting a white ball) = 0.
P(getting a white ball) = `"No. of favourable outcomes"/"No. of possible outcomes"` = `0/6 = 0`
Hence, the probability of getting a white ball = 0.
(ii) There are 6 identical black balls.
∴ No. of favourable outcomes (of getting a black ball) = 6.
P(getting a black ball) = `"No. of favourable outcomes"/"No. of possible outcomes"` = `6/6 = 1`
Hence, the probability of getting a black ball = 1.
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