Find the term:`1.2+1.7+2.2+…. `To the 40th term.

Find the term: 20+18+16+…. To the 16th term.

Find the sum of the following series: 2+1+1/2+1/(2^2)…. to the nth term.

Find the sum of the following series: 1+1.04+(1.04)^2+….. to the 20th term.

An AP consists of 50 terms of which 3rd term is 12 and the last term is 106.Find the 29th term.

Find the sum of the following series: 1+3+9+…. to the 9th term.

Find the 31st term of an AP whose 11th term is 38 and the 16th term is 73.

In a certain A.P., the 24th term is twice the 10th term. Prove that 72th term is twice of 34th term.

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)

Find the sum of -7-4-1 + 2…. to 20th term.

Find the term: n+(n-1)+(n-2)….+(r) terms .