If a1,a2,a3,.......... are in AP then ap,aq,ar are in AP if p,q,r are in:
If a1,a2,a3... are in A.P, then ap,aq,ar are in A.P if p, q, r are in
If a1,a2,a3,a4 are in AP, then
Let a1,a2,a3......... are in A.P such that ap, aq,ar are in both A.P and GP then aq:ap is equal to