Find the sum of first 20 terms of the arithmetic progression having the sum of first 10 terms as 52 and the sum of the first 15 terms as 77.

Find the sum of the first 20 terms of the arithmetic progression having the sum of first ten terms as 52 and the sum of the first 15 terms as 77.

If the sum of the first 4 terms of an arithmetic progression is p, the sum of the first 8 terms is q and the sum of the first 12 terms is r, express 3p+r in terms of q.

If the sum of the first 23 terms of an arithmetic progression equals that of the first 37 terms , then the sum of the first 60 terms equals .

If the sum of the first 23 terms of an arithmetic progression equals that of the first 37 terms , then the sum of the first 60 terms equals .

If the sum of first 8 terms of an Arithmetic progression is 136 and that of first 15 terms is 465, then find the sum of first 25 terms. OR Ths sum of the 5th and 9th terms of an A.P. is 40 and the sum of the 8th and 14th term is 64. Find the sum of the first 20 terms.

If the sum of first 11 terms of an arithmetic progression equal that of the first 19 terms, Then, what si the sum of first 30 terms?

What is the sum of the first 12 terms of an arithmetic progression, if the first term is 3 and the last term is 47?