Question

first term and common difference of an A. P are 6 and 3 respectively find S27
a=6,d=3,S27=?​

Answer 1

Step-by-step explanation:

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

S27=27/2(2*6+(27-1)3)

=27/2(12+26(3))

=27/2(90)

=1215.

Answer 2

Answer:

answer attached in photo