If the pth term of an A.P. is 1/q and qth term is 1/p and sum of pq term is 25pq then find the value of pq .

If p^th term of an AP is 'q' and q^th term is 'p', where p ne q find r^th term.

If the m^th terms of an AP is 1/n and the n^th term is 1/m , prove that the sum of the first mn terms is 1/2(mn+1)

The sum of the first 4 terms of an A.P. is 56. The sum of the last 4 terms is 112. If its first term is 11, then find the number of terms.

If the first term of a G.P is 1 and the sum of 3^(rd) and 5^(th) terms is 90 then the positive common ratio of the G.P. is

If the sum of p terms of an AP is the same as the sum of its q terms, show that the sum of its (p+q) terms is zero.

Suppose that the first and the 5^(th) terms of an A.P. are-14 and 2 respectively If the sum of the terms of the A.P is 40, find the number of terms in the A.P.

Find the sum of 32 terms of an AP whose third term is 1 and the 6^th term is -11.

In an A.P., if 5 ^(th) term is (1)/(7) and 7^(th) term is (1)/(5), then the sum of first 35 terms is

The first term of a G.P. is 1. The sum of the third term and fifth term is 90. Find the C.R of the G.P

If the sum of n terms of an A.P is 3n^2+5n and its m^(th) term is 164. Find the value of m.