JEE Mains · Maths · STD 12 - 13. probability
The probability of a man hitting a target is \(\frac{1}{10}\). The least number of shots required, so that the probability of his hitting the target at least once is greater than \(\frac{1}{4},\) is
- A \(2\)
- B \(3\)
- C \(4\)
- D \(5\)
Answer & Solution
Correct Answer
(B) \(3\)
Step-by-step Solution
Detailed explanation
We have, \(1-(\) probability of all shots result in failure \()>\frac{1}{4}\) \(\Rightarrow 1-\left(\frac{9}{10}\right)^{n}>\frac{1}{4}\) \(\Rightarrow \frac{3}{4}>\left(\frac{9}{10}\right)^{n} \Rightarrow n \geq 3\)
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