Let `S_n` denote the sum of first `n` terms of an A.P. If `S_(2n)=3S_n ,` then find the ratio `S_(3n)//S_ndot`

Let s_(n) denote the sum of first n terms of an A.P. and S_(2n) = 3S_(n) . If S_(3n) = kS_(n) then the value of k is equal to

Let S_(n) denote the sum of first n terms of an A.P. If S_(4) = -34 , S_(3) = - 60 and S_(6) =- 93 , then the common difference and the first term of the A.P. are respectively.

Let S_(n) denote the sum of the first n terms of an AP. If S_(4) = 16 and S_(6) = -48 , then S_(10) is equal to

If S_n=n P+(n(n-1))/2Q ,w h e r eS_n denotes the sum of the first n terms of an A.P., then find the common difference.

If the sum of n terms of a G.P. is 3(3^(n+1))/(4^(2n)) , then find the common ratio.

If the sum of n terms of a G.P. is 3-(3^(n+1))/(4^(2n)) , then find the common ratio.

If S_n denotes the sum of first n terms of an A.P. and (S_(3n)-S_(n-1))/(S_(2n)-S_(2n-1))=31 , then the value of n is 21 b. 15 c.16 d. 19

Find the sum of the first 30 terms of an A.P. whose nth term is 3 + 2n.

Find the sum of the first 28 terms of an A.P. whose nth term is 4n-3.