Arithmetic Mean Definition:
     Arithmetic mean is commonly called as average.Mean or Average is defined as the sum of all the given elements divided by the total number of elements.

  Formula:
      Mean = sum of elements / number of elements
              = a1+a2+a3+.....+an/n

  Example: To find the mean of 3,5,7.
      Step 1: Find the sum of the numbers.
          3+5+7 = 15

      Step 2: Calculate the total number.
          there are 3 numbers.

      Step 3: Finding mean.
          15/3 = 5