Question

Determine the sum of the first 27 even Natural Numbers.
378
2,700
270
756

Answer 1

this is called AP arithmetic progression

2, 4, 6.........

sn=n/2(2a+(n-1)d)

S27=

`(27)/(2 ) (2 * 2 + (27 - 1)2)`

`(72)/(2) (4 + (26 * 2)`

`(27)/(2) (4 + 52)`

`(27)/(2) * 56`

`27 * 28`

=756