• MEAN, MEDIAN, AND MODE ARE ALL TYPES OF 
                    AVERAGES. TOGETHER WITH RANGE, THEY 
   EXPLANATI        HELP DESCRIBE THE DATA. DEFINITIONS: MEAN - 
   ON &             WHEN PEOPLE SAY "AVERAGE" THEY USUALLY 
                    ARE TALKING ABOUT THE MEAN. YOU CAN 
   DEFINITION       FIGURE OUT THE MEAN BY ADDING UP ALL THE 
                    NUMBERS IN THE DATA AND THEN DIVIDING BY 
                    THE NUMBER OF NUMBERS.
     EXPLANATI        • THE MEDIAN IS THE VALUE SEPARATING THE HIGHER 
                       HALF OF A DATA SAMPLE, A POPULATION OR A 
     ON MEDIAN         PROBABILITY DISTRIBUTION FROM THE LOWER HALF. 
                       IN SIMPLE TERMS, IT MAY BE THOUGHT OF AS THE 
                       "MIDDLE" VALUE OF A DATA SET. FOR EXAMPLE, IN 
                       THE DATA SET {1, 3, 3, 6, 7, 8, 9}, THE MEDIAN IS 6, 
                       THE FOURTH NUMBER IN THE SAMPLE. THE MEDIAN 
                       IS A COMMONLY USED MEASURE OF THE PROPERTIES 
                       OF A DATA SET IN STATISTICS AND PROBABILITY 
                       THEORY. 
        HOW TO CALCULATE 
             THE MEAN
      •THE MEAN 
      •WHEN PEOPLE TALK ABOUT STATISTICAL 
      AVERAGES, THEY ARE REFERRING TO THE MEAN. 
      TO CALCULATE THE MEAN, SIMPLY ADD ALL OF 
      YOUR NUMBERS TOGETHER. NEXT, DIVIDE THE 
      SUM BY HOWEVER MANY NUMBERS YOU ADDED. 
      THE RESULT IS YOUR MEAN OR AVERAGE SCORE
              For example, let's say you have four test scores: 15, 
              18, 22, and 20. To find the average, you would first 
              add all four scores together, then divide the sum by 
              four. The resulting mean is 18.75. Written out, it 
              looks something like this:
              (15 + 18 + 22 + 20) / 4 = 75 / 4 = 18.75
          HOW TO CALCULATE THE MEDIAN
      • THE MEDIAN 
      • THE MEDIAN IS THE MIDDLE VALUE IN A DATA SET. TO CALCULATE IT, 
       PLACE ALL OF YOUR NUMBERS IN INCREASING ORDER. IF YOU HAVE AN 
       ODD NUMBER OF INTEGERS, THE NEXT STEP IS TO FIND THE MIDDLE 
       NUMBER ON YOUR LIST. IN THIS EXAMPLE, THE MIDDLE OR MEDIAN 
                         3, 9, 15, 17, 44
       NUMBER IS 15:
         If you have an even number of data points, calculating the 
         median requires another step or two. First, find the two middle 
         integers in your list. Add them together, then divide by two. The 
         result is the median number. In this example, the two middle 
         numbers are 8 and 12
              3, 6, 8, 12, 17, 44
              Written out, the calculation would look like this:
              (8 + 12) /  2  = 20 / 2 = 10