How to Calculate Averages (Mean, Median, Mode)

Step-by-Step Guide

1. 1

   Step 1: Determine that you need to find the mean.

   The mean is just one measure of central tendency, and is what most people think of when they think of the term average.
   
   It is best to use the mean when you need to find the average of a data set that does not have an outlier.
   
   An outlier is a number that is outside the normal range of distribution.
   
   For example, in the series 1, 289, 333, 303, the clear outlier is
   1.
   
   If the series has an outlier, it is better to calculate the median to find the central tendency.
2. 2

   Step 2: Determine the series of numbers you need to calculate the mean for.

   This is usually a set of three or more numbers.
   
   Make sure to include all the numbers in the series, including 0 and negative numbers.
   
   For example, you might need to find the average low temperature in Chicago in the first week of January.
   
   The temperatures might be
   -1, 15, 0, 12, 15, 8, and 17 degrees. , It might be helpful to use a calculator or spreadsheet software like Microsoft Excel if you are working with a large data set.
   
   To learn more about using Excel to find the average, read Calculate Averages in Excel.
   
   For example, if your series is
   -1, 15, 0, 12, 15, 8, 17, you would calculate:−1+15+0+12+15+8+17=66{\displaystyle
   -1+15+0+12+15+8+17=66} , Don’t forget to count any data points that have a value of
   0.
   
   This will give you the average of your series of numbers.
   
   For example, there are 7 numbers in the series
   -1, 15, 0, 12, 15, 8,
   17.
   
   So, you should divide their sum (66) by 7:66÷7=9.43{\displaystyle 66\div 7=9.43}So, the mean, or average, of the series is
   9.43.
3. 3

   Step 3: Add together all the numbers in the series.

4. 4

   Step 4: Divide the sum of the numbers by how many numbers are in the series.

Detailed Guide

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