Average

 In this lesson, we're going to learn about average. Average means the median (middle score) in sets of scores.
Therefore it's not difficult to see that average of  two scores 10 and 14 is 12. Another way of figuring out is add two score and divide by the number of scores.

The first example is, find the average of 6, 9, 2 and 7.

           Average= 6+9+2+7/4                                                      Find the total of 4 scores and
          =24/4                                                                               divide total by 4.
          =6 

 The second example is Jimmy wrote 5 numbers on a separate paper, the scores are 56, 45,75, 23 and 77.
   
            Average = 56+45+75+23+77/5
                         = 276/5                                                         Find the total of 5 scores
                         = 55.2                                                          and divide the total by 5.

 The third example is The average of 6 number is 54. A fifth number is added onto the total and the new average is 95. What is the fifth number?

           Total of first 4 numbers = 4 x average = 6 x54 = 324
           Total of 5 numbers = 5 x new average = 5 x 95 = 475
           The fifth number is therefore 475 - 324 = 151.


Fourth and last example is, My average in 5 maths test is 85%. If I scored 96% in my sixth test, what is my new average?


                      Total marks in first 5 tests = 5 x average = 5 x 85 = 425
                      Total marks in six tests = 425 + new mark = 425 + 96 = 521

                      New average = 521/6
                                           = 86.8%
                                           =87%  (To the nearest whole number)