# ck12.org 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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**Video Rating: / 5**

Wouldn't 1 SD get you .34?

THANK YOU VERY MUCH 🙂

I found this very useful.

o— = 1.1 kgs right? and not 1.1 gms

*Tears*thank you!!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.

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?

Thanks for sharing!

Thanks man! thanks for sharing!!

awesome.. u just made it so much simpler

This is amazing! Great work!

Each of the legs of the 68% region are Left=34% & Right=34%, not 32%.