Question

Sum of all the natural no. 100 to200 which is mutiply by3

Answer 1

Your answer is 4950...

Answer 2

a = 102, n=33, d=3

We know that, S = n(2a + (n-1)d)/2

                            = 33 (2 * 102 + (33-1)*3)/2

                            = 33 ( 204 + 96)/2

                             = 4950.


Hope this helps!