Question

If sum of n terms of A.P. is Sn and

S2n=3Sn then S3n :Sn will be

(a) 10 (b) 11 (c) 6 (d) 4​

Answer 1

Answer:

b)6

S3n=3n(3n+1)/2........(1)

Sn=n(n+1)/2...........(2)

Dividing (1) from (2) and substituting the value of n as 1, we get the ans as 6.