Let `a_1,a_2,a_3,……,a100` be an arithmetic progression with `a_1=3 – InterviewSolution

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1.	Let `a_1,a_2,a_3,……,a100` be an arithmetic progression with `a_1=3 and S_p=Sigma_(i=1)^(p) a_i, 1 le p le 100`. For any integer n with `1 le n le 20 , let m=5 n`. If `(S_m)/(S_n)` does not depend on .n then `a_2` is _________.
Answer» Correct Answer - 6 `a_1,a_2,a_3,.....,a_100` is an A.P `a_1+3,S_p=underset(i=1)overset(p)Sigma a_a,1 le p le 100` `(S_m)/(S_(n))=(S_(5n))/(S_n)=((5n)/(2)(6+(5n-1)d))/(n/2(6+(n-1)d))` `S_m/S_n` is independent of n of 6-d =0 `rArr` d=6

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