" Fifth term of an "A.P." is "7" then sum of first "9" terms is "..........

7^(th) term of an A.P. is 40. Then, the sum of first 13 terms is

The 5^(th) term of an AP is 50. Find the sum of first 9 terms.

The twelfth term of an A.P. is (-13) and the sum of its first four terms is 24, find the sum of first 12 terms of the A.P.

If the first term of an A.P. is 3 and the sum of its first 25 terms is equal to the sum of its next 15 terms, then the common difference of this A.P. is:

If the first term of an A.P. is 2 and the sum of the first five terms is equal to one fourth of the sum of the next five terms, find (i) the 20th term (ii) the sum of first 30 terms.

The first term of an A.P. is 100 and the sum of whos f first 6 terms is 5 xx the sum of the next 6 terms,then the c.d. is

If the first term of an A.P. is 100 and the sum of its first 6 terms is five times the sum of the next 6 terms then its common difference is

The sum of the first five terms of an A.P. and the sum of the first seven terms of the same A.P. is 167. If the sum of first 10 terms of this A.P. is 235, find the sum of its first twenty terms.