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प्रश्न
A box contains 6 red marbles numbered 1 through 6 and 4 white marbles numbered from 12 through 15. Find the probability that a marble drawn is white .
उत्तर
Total number of marbles = (6 + 4) = 10
Let S be the sample space.
Then n(S) = number of ways of selecting one marble out of 10 = 10C1 = 10 ways
Let E1 = event of getting a white marble
∴ n(E1) = 4C1 = 4
Hence, required probability = \[\frac{^{4}{}{C}_1}{^{10}{}{C}_1} = \frac{4}{10} = \frac{2}{5}\]
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