A) 3
B) 4
C) 5
D) None of these
Correct Answer: B
Solution :
Probability of getting at least one head in \[n\] tosses \[=1-{{\left( \frac{1}{2} \right)}^{n}}\ge 0.9\Rightarrow {{\left( \frac{1}{2} \right)}^{n}}\le 0.1\Rightarrow {{2}^{n}}\ge 10\Rightarrow n\ge 3\] Hence least value of \[n=4.\]You need to login to perform this action.
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