The sum of first four terms of an A.P is 56. the sum of last four terms is 112. If the first term is 11. find the number of terms.

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

The first term of an A.P. is 5, the common difference is 3 and the last term is 80, find the number of terms.

The sum of n terms of an A.P. is 136, the common difference is 4 and the last term is 31, find the number of terms.

If the sum of first 7 terms of an AP is 49 and that of 17, terms is 289, find the sum of first n terms.

If first term is 2 and last term is 10 then find the sum of 5th term

The sum of first three terms of a G.P. is 7 and the sum of their squares is 21. Determine the first five terms of the G.P.

The sum of first three terms of a G.P. is 16 and the sum of the next three terms is 128. Determine the first term, the common ratio and the sum to n terms of the G.P.

The sum of first ten terms of an A.P. is 155 and the sum of first two terms of a G.P. is 9. The first term of the A.P. is equal to the common ratio of the G.P., and the first term of the G.P. is equal to the common difference of the A.P. Find the two progressions.