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JEE Mains · Maths · STD 12 - 13. probability
The probability of a man hitting a target is \(\frac{2}{5}\). He fires at the target \(k\, times\) (\(k\), a given number). Then the minimum \(k\), so that the probability of hitting the target at least once is more than \(\frac{7}{10}\), is
- A \(3\)
- B \(5\)
- C \(2\)
- D \(4\)
Answer & Solution
Correct Answer
(A) \(3\)
Step-by-step Solution
Detailed explanation
\(\quad \frac{2}{5}+\frac{3}{5} \times \frac{2}{5}+\left(\frac{3}{5}\right)^{2} \times \frac{2}{5}+\ldots \ldots+\left(\frac{3}{5}\right)^{k} \cdot \frac{2}{5}>\frac{7}{10}\)…
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