JEE Mains · Maths · STD 12 - 13. probability
Minimum number of times a fair coin must be tossed so that the probability of getting at least one head is more than \(99\%\) is
- A \(8\)
- B \(6\)
- C \(7\)
- D \(5\)
Answer & Solution
Correct Answer
(C) \(7\)
Step-by-step Solution
Detailed explanation
\({1-\left(\frac{1}{2}\right)^{n}>\frac{99}{100}} \) \({\Rightarrow\left(\frac{1}{2}\right)^{n}<\frac{1}{100}} \) \({\Rightarrow n=7}\)
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