If middle term of `n` odd numbered terms A.P.is `5` ,then: `S_n``=`

Prove that the sum of an odd number of terms in A.P is equal to the middle term mutiplied by the number of terms

If the middle term amongst any odd number (n) consecutive terms of an A.P, is m, then their sum is (a) 2m^2n (b) (mn)/2 (c) mn (d) mn^2

If s_(n), the sum of first n terms of an A.P.is given by S_(n)=5n^(2)+3n, then find its n^(th) term.

If the sum of first 6 terms of A.P.is 96 and sum of first 10 terms is 240 ,then find the sum of n terms of A.P.

If the pth term of an A.P.is q and the qth term is p, then find its rth term.

An A.P., and a H.P. have the same first and last terms and the same odd number of terms. The middle terms of the three series are in

191.If the sum of first n terms of an A.P.is Zero,then the sum of next m terms,where a is the first term of the A.P.is

If the sum of n terms of an A.P.is 2n^(2)+5n then its nth term is 4n-3 b.3n-4 c.4n3 d.3n+4

The number of terms of an A.P.is even; the sum of the odd terms is 310; the sum of the even terms is 340 ; the last term exceeds the first by 57. Find the number of terms and the first terms of series.