Obtain the sum of 56 terms of an A.P. whose `19^(th) and 28^(th)` terms are 52 and 148 respectively.

Obtain the sum of the first 56 terms of an A.P. whose 19th and 38th terms are 52 and 148 respectively.

Obtain the sum of 56 terms of an A.P whose 19th and 38th term are 52 and 148 respectively.

Obtain the sum of the first 56 terms of an A.P. Whose 18th and 39th terms are 52 and 148 respectively. (1) Usint t_(18) and t_(39) find two simultaneous equations in variables a and d. (2) Using these equations, find S_(56)

Find the sum of first 17 terms of an AP whose 4th and 9th terms are -15 and -30 , respectively.

Find the sum of first 17 terms of an AP whose 4th and 9th terms are -15 and -30 , respectively.

Find the nth term of an A.P. whose 6th and 8th terms are 12 and 22 respectively :

Find the sum to 'n' terms of an A.P. whose 7^(th) term is 30 and 13^(th) term is 54.

The first term of an A.P. whose 8th and 12th term are 39, 59 respectively.

Find the sum of 32 terms of an A.P. whose third term is 1 and 6^(th) term is -11.