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average of first n natural numbers

The natural numbers are 1,2,3,4,5,. . . . . .
now we will see the sum of natural numbers
                      sum of first 3 natural numbers= 1+2+3=6
the above can be written as
                     sum of first 3 natural numbers= 1+2+3=6=3(3+1)/2
                     sum of first 4 natural numbers= 1+2+3+4=4(4+1)/2
                     then sum of n natural numbers=1+2+3+......n terms=n(n+1)/2

then the average formula = sum of elements/no of elements
                    the average of n natural numbers= sum of elements/ no of elements
                                                                        =(n(n+1)/2)/n
                                                                        =n(n+1)/2xn
                                                                        =(n+1)/2
 THE AVERAGE OF FIRST N NATURAL  NUMBERS=(n+1)/2

The average of first 5 natural numbers
                                 sum of 5 natural numbers=1+2+3+4+5=15
                                 no of elements = 5
                                 average = 15/5 =3

by formula  = average of first 5 natural numbers = (n+1)/2 =(5+1)/2
                                                                                              =6/2
                                                                                              =3

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