Mathematics · 2019
JEE Main · 8 April 2019, Shift 2 · Q87
The minimum number of times one has to toss a fair coin so that the probability of observing at least one head is at least 90% is:
The minimum number of times one has to toss a fair coin so that the probability of observing at least one head is at least $\displaystyle 90$% is :
Official answer
(3)
$\displaystyle 4$
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JEE Main 2019 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.