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Question
An integer is chosen between 0 and 100. What is the probability that it is divisible by 7?
Solution
The number of integers between 0 and 100 is n(S) = 99
Let E1 = Event of choosing an integer which is divisible by 7
= Event of choosing an integer which is multiple of 7
= {7, 14, 21, 28, 35, 42, 49, 56, 63, 70, 77, 84, 91, 98}
∴ n(E1) = 14
∴ `P(E_1) = (n(E_1))/(n(S)) = 14/99`
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