Coin count past two sigma
A fair coin is flipped 100 times. Using the normal approximation and the 68–95–99.7 rule, approximately what percent of the time do you get more than 60 heads? Give a percent to one decimal.
Show hints (2)+
- Find the mean and the sd ; where does fall?
- The band is two-sided - one tail is half the leftover.
Answer
Reveal answer →Final answer
2.5 (± 1)
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Asked at: Timed Mental-Math & Sequences, ETF Market-Making