k12.org exercise: Standard normal distribution and the empirical  Khan Academy  Summary and Q&A
TL;DR
The video discusses a problem involving the normal distribution and applies the empirical rule to determine the percentage of data and order the given values.
Questions & Answers
Q: What is the mean of a standard normal distribution?
The mean of a standard normal distribution is 0.
Q: How can the empirical rule be used to estimate percentages under a normal distribution?
The empirical rule states that approximately 68% of data falls within one standard deviation, 95% within two standard deviations, and 99.7% within three standard deviations. By using this rule, you can estimate percentages without a normal distribution table.
Q: What is the percentage of data below 1 in a standard normal distribution?
Using the empirical rule, the area under the bell curve up to 1 is approximately 68%. This is because 68% of data falls within one standard deviation of the mean.
Q: How can we determine the percentage of data above 2 in a standard normal distribution?
By applying the empirical rule, we find that 95% of data falls within two standard deviations of the mean. Therefore, the remaining area beyond two standard deviations is 5%, which is divided equally on both tails, giving us 2.5% for the percentage of data above 2.
Summary & Key Takeaways

The video introduces problem number 4 from a free AP Statistics FlexBook by ck12.org.

It explains how to draw a standard normal distribution and identifies the mean as 0 and the standard deviation as 1.

The video demonstrates how to use the empirical rule to calculate the percentage of data and order the given values.