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प्रश्न
A number is selected at random from the numbers 1 to 30. What is the probability that the selected number is a prime number?
पर्याय
`2/3`
`1/6`
`1/3`
`11/30`
उत्तर
Total number of outcomes = 30.
Prime numbers in 1 to 30 are 2, 3, 5, 7, 11, 13, 17, 19, 23 and 29.
Number of favourable outcomes = 10.
∴ P(getting a prime number) = `("Number of favourable outcomes")/"Number of all possible outcomes"`
`=10/30 = 1/3`
Thus, the probability that the selected number is a prime number is `1/3`.
Hence, the correct answer is option (c).
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