If 27 + 24 + 21 + ... to n terms = 132, find n.

The first term and common difference of an A.P. are respectively 4 and 2. If the sum up to n terms is 88, find n.

The first term and common difference of an A.P. are respectively -2 and -4. If the sum upto n terms is —288, find n.

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

The pth term of an A.P. is —q and qth term is -p. If the nth term is zero, find n.

If the sum of first nine terms of an A.P is 171 and that of first 24 terms is 996,find the sum of first 41 terms.

Can zero be a term of an A.P. whose eleventh term is 62 and 21th term is 32 ? (Hint : Taking the nth term to be zero, find n)

If the sum to n terms of the A.P.-9,-1,7, ... is 2175, find n.

If the sum of the first n terms of an AP is 4n-n^2 ,what is the first term(that is S_1 )?What is the sum of first two terms?What is the second term?Similarly,find the 3rd,the 10th and nth terms.

If the sum of three consecutive terms of an A.P is 21 and the sum of the squares of the terms is 165,find the terms.

The sum of first nine terms of an A.P. is 171 and that of 24 terms is 996. Find the sum of first 16 terms.