Question

What is the sum of all even numbers from 100 to 200

Answer 1

Heya !!

Here is your answer..

Given, a = 100 , n = 51 and l = 200

Sn = ?

==> n/2 ( a + l )

==> 51/2 ( 100 + 200 )

==> 51/2 (300)

==> 51 * 150

==> 7650

Hope it helps.

Answer 2

Solution:-

100 , 102,104, 106...............200

= mean diffrence ( d) = 2
=firts term (a) = 100 (n = 200)

= 200 = 100+ (n-1)2

= n-1 = 50 = n = 51

sum = 51/2 x (first term +last term)

= 51/2 ×(100+200)

= 51×150

= (7650)ans