Mean, Median, Mode, Range

Date: 11/23/97 at 20:13:14
From: Jamie Higham
Subject: Math definitions

What are definitions for mean, median, mode, and range?

Date: 11/23/97 at 21:06:14
From: Doctor Scott
Subject: Re: Math definitions

Hi Jamie!

Let's define each of the words and give an example.  

Consider the set of numbers  80, 90, 90, 100, 85, 90.  They could be 
math grades, for example.

The MEAN is the arithmetic average, the average you are probably used 
to finding for a set of numbers - add up the numbers and divide by how 
many there are:  (80 + 90 + 90 + 100 + 85 + 90) / 6 = 89 1/6.

The MEDIAN is the number in the middle. In order to find the median, 
you have to put the values in order from lowest to highest, then find 
the number that is exactly in the middle:

        80   85   90   90   90   100
                     ^
     since there is an even number of values, the MEDIAN is 
     between these two, or it is 90. Notice that there is 
     exactly the same number of values ABOVE the median as 
     BELOW it!

The MODE is the value that occurs most often. In this case, since 
there are 3 90's, the mode is 90. A set of data can have more than one 
mode.

The RANGE is the difference between the lowest and highest values. 
In this case 100 - 80 = 20, so the range is 20. The range tells you 
something about how spread out the data are. Data with large ranges 
tend to be more spread out.

-Doctor Scott,  The Math Forum
 Check out our web site!  http://mathforum.org/dr.math/