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Question
20 cards are numbered from 1 to 20. One card is drawn at random. What is the probability that the number on the cards is greater than 12?
Solution
Clearly, the sample space is given by S = {1, 2, 3, 4, 5........19, 20}.
i.e. n(S) = 20
Let E4 = event of getting a number greater than 12
Then E4 = {13, 14, 15, 16, 17, 18, 19, 20}
i.e. n(E4) = 8
Hence, required probability = P(E4) = \[\frac{8}{20} = \frac{2}{5}\]
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