Question

18/07/20
0
Find the sum of first
first 15 terms of the
A.P. 8, 77 162 163
allt​

Answer 1

Answer:

n = 15

a= 8

d = 77-8 = 69

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

= 15/2 (2×8+(15-1)69)

= 15/2 (16+14×69)

=15/2×982

sn= 7365