There are 20 terms in an arithmetic sequence. Sum of the first and last terms is 88.
What is the sum of the 2nd and `19^(th)` terms?

In an AP, the 5th term is 30 and 12th term is 65. What is the sum of first 20 terms?

There are five terms in an arrithmetic progression. the Sum of these terms is 55, and the fourth term is five more than the sum of the first two terms.Find the terms of the Arithmaetic progression.

In an A.P. if the 12^(th) term is -13 and the sum of the first four terms is 24, what is the sum of the first 10 terms?

The middle term of an Arithmetic series consisting of 25 terms is 20. Find the sum of the series.

If the first four terms of an arithmetic sequence are a,2a,b and (a-6-b) for some numbers a and b, find the sum of the first 100 terms of the sequence.