Question

please give answer of this q​

Answer 1

Answer:

It is given that,

First term (a) = 6

Common difference (d) = 3

S_{n} = n/2 * (2a + (n - 1) * d)

.S 27 = 27 2 (2(6)+(27-1)(3))

= 27 2 (12+26(3))

= 27 2 (12+78)

= 27 2 *90

=1215

Hence, S_{27} = 1215 .