http://www.ck12.org Chapter 1. An Introduction to Analyzing Statistical Data
There are 22 students in this class and the total number of children in all of their houses is 55, so the mean of
this data is 55÷ 22 = 2 .5. Statisticians use the symbolXto represent the mean whenXis the symbol for a single
measurement. It is pronounced “xbar.”
It turns out that the model that you created balances at 2.5. In the pictures below, you can see that a block placed at
3 causes the graph to tip left, and while one placed at 2 causes the graph to tip right. However, if you place the block
at about 2.5, it balances perfectly!