Seventh term of an A.P. ios 40. Then the sum of its first 13 items is-

7th term of an A.P. is 40. then the sum of the first 13 terms is

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

If the 7^(th) term of n A.P is 40. Then the sum of its first 13 terms is

The sum of the first 8 terms of an A.P. is 100 and the sum of its first 19 terms is 551. Find the first term and the common difference of the AP.

The seventh term of an A.P. is 20 and the sum of first twenty terms is 610. Find the tenth term and the sum of first fifteen terms.

The first term of an A.P. is 20 and the sum of its first seven terms is 2100, find the 31st term of this A.P.

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 twelfth term of an A.P. is (-13) and the sum of its first four terms is 24, find the sum of first 10 terms of the A.P.

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: