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Average of first n even numbers

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Even numbers are 2,4,6,8,10,….
Average = sum of elements/ no of elments
Now we will see the sum of elements:
Sum of first 2 even numbers: 2+4= 6= 2(2+1)
Sum of first 3 even numbers: 2+4+6= 12= 3(3+1)
Sum of first 4 even  numbers: 2+4+6+8=20= 4(4+1)
Sum of first 5 even numbers: 2+4+6+8+10 = 30 = 5(5+1)
Sum of first n even numbers: 2+4+6+8+10+. . . . .  n numbers= n(n+1)
Now we will see average:
Average of first 2 even numbers= (2+4)/2
                                                          = 6/2
                                                                =3
Average of first 3 even numbers= (2+4+6)/3
                                                          = 12/3
                                                                =4
Average of first 4 even numbers= (2+4+6+8)/4
                                                          = 20/4
                                                                =5
Average of first 5 even numbers= (2+4+6+8+10)/5
                                                          = 30/5
                                                                =6
Average of first n even numbers= (2+4+6+8+10+ . . .  . . n numbers)/n
                                                          = n(n+1)/n
                                                                =n+1
Since from above formula we can write directly as below:
Average of first 2  even numbers = n+1 = 2+1= 3
Average of first 3 even  numbers = n+1 = 3+1=4
Average of first 4 even  numbers = n+1 = 4+1=5
Average of first 5 even numbers = n+1 = 5+1=6





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