Q17 of 202 Page 10

If S_r denotes the sum of the first r terms of an A.P. Then, S_3n: (S_2n — S_n) is

S_2n = (2a + (2n–1) d)

S_n = (2a + (n–1)d)

S_3n = (2a + (n–1)d)

S_2n –S_n = (2a + (2n–1) d) – (2a + (n–1)d)

= (2a + (n –1) d)

S_3n: (S_2n — S_n) = (2a + (n–1)d) : (2a + (n –1) d)

= 3

If S_n denote the sum of the first n terms of an A.P. If S_2n = 3S_n, then S_3n : S_n is equal to

In an AP, S_p = q, S_q = p and S_r denotes the sum of first r terms. Then, S_{p + q} is equal to

If the first term of an A.P. is 2 and common difference is 4, then the sum of its 40 terms is

The number of terms of the A.P. 3, 7, 11, 15, ... to be taken so that the sum is 406 is

If Sr denotes the sum of the first r terms of an A.P. Then, S3n: (S2n — Sn) is