12.2+Mean

Section 12.2 - Mean
When you think of "average", it most often requires you to calculate the mean or "arithmetic mean", even if it doesn't specify this method.


 * To calculate the mean of a set of values, add up the values and divide by the number of values. **

12, 3, 0, -4, 3, -6, 10 = 18 / 7 = 2.57


 * Weighted Mean**

There is a different version of arithmetic mean that requires a bit more work. Consider your grade point average (GPA). It is an average of the grades for your classes based on a 4.0 scale. However, they don't weight each class the same -- an A in a four credit class counts more than an A in a one credit class. To calculate the weighted mean for GPA, multiply the value of the grade by the number of credits for that class, then divide by the total number of credits rather than the total number of classes.




 * Chapter Twelve Practice Problems**

**Where to from here?**
12.1 Average 12.2 Mean 12.3 Median 12.4 Mode Chapter Twelve Summary Chapter Twelve Homework