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Question
Choose the correct option from the given alternatives:
The probability of a shooter hitting a target is `3/4` How many minimum numbers of times must he fire so that the probability of hitting the target at least once is more than 0·99?
Options
2
3
4
5
Solution
4
Hint:
P(X ≥ 1) > 0.99
∴ 1 - P(X = 0) > 0.99
∴ P(X = 0) < 0.01 = `1/100`
∴ `"^nC_0 (3/4)^0 (1/4)^n < 1/100`
∴ `(1/4)^n < 1/100`
∴ n = 4
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