Question

if a=3 and t6=27 find the sum of first six terms​

Answer 1

Answer:

t6 = 27

t1 = 3

sn = n/2(t1 +tn)

s6=6/2(t1 +t6)

s6 = 3( 3 + 27)

s6 = 3 (30)

s6 = 90