normal distribution problems: Empirical rule | Probability and Statistics | Khan Academy

Using the empirical rule (or 68-95-99.7 rule) to estimate probabilities for normal distributions

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12 replies
  1. ThatRogueSTEVE
    ThatRogueSTEVE says:

    This is what I have been looking for! Finally a few videos outlining how to complete actual questions. Theory is great to know, but it really wasn't helping me actually answer any of my questions in assessments.

  2. Maran Hammoud
    Maran Hammoud says:

    Okay, I understand how you would get this. But I have a problem with the same concept but I cant seem to get it! 
    1. The pulse rates of healthy adults are normally distributed with mean 72
    and standard deviation of 5.
    a) What percentage of healthy adults have a pule rate over 80? (Hint:
    You may want to use Excel here.)
    at the 95% mark it's 82. do I still use the same method? Is there more calculations?


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