Quandaries
and Queries 

Hi I have a task to complete, which is to calculate the mean and standard deviation of something. I have done this but am then asked to write a short explanation of my findings. I know what the mean is about, and I thought
I knew what the standard deviation meant too  shows the variation
from the mean. Many thanks. 

Hi Rebecca, If you have a collection of data from a Normal Distribution then approximately 66% of the data should fall within one standard deviation of the mean. For exmple if the mean is 6 and the standard deviation is 1.2 then approximately 66% of the data is between
and
The same approximation is usually true if the data is approximately normally distributed and the data set is reasonably large. By "approximately normal" it is usually enough that a histogram of the data be approximately bell shaped and symmetric. Penny 

