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Question
What is the probability of the event that a number chosen from 1 to 50 is a prime number?
Options
`3/10`
`1/2`
`1/4`
`3/25`
Solution
`3/10`
Explanation:
S = {1, 2, ..... , 50}
∴ n(S) = 50
Let A be the event of getting a prime number.
∴ A = {2, 3, 5, 7, 11, 13, 17 ,19, 23, 29, 31, 37, 41, 43, 47}
∴ n(A) = 15
∴ P(A) = `("n"("A"))/("n"("S")) = 15/50 = 3/10`
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