Find the sum of first 11 terms of the sequence 20,25,30.......

The algebraic form of an arithmetic sequence is 8n+7 . Find the sum of first 30 terms of this sequence.

23rd term of an arithmetic sequence is 32.35th term is 104. Then Find the sum of first 35 terms of this sequence.

The algebraic form of an arithmetic sequence is 6n+5. Find the sum of first 20 terms of this sequence?

Find the sum to n terms of the sequence 8,88,888,8888…

What is the sum of first 20 natural. numbers? b) Find the sum of .first 20 terms of 4,8 , 12,.... c) If 3 is added to each term in the above sequence, write down the algebraic expression of the new sequence. d) Find the sum of first 20 terms of the new sequence.

Algebraic form of an arithmetic sequence is 6n+3 a) Find the sum of first 20 terms of the sequence: b) Write the algebraic expression of the sum.

Find the sum of the first n terms of the arithmetic sequence 1/n,3/n,5/n,7/n ,.......

Find the sum to n terms of the sequence 4+44+444+…….

Arithmetic sequence is 1/7,2/7,3/7… What is the sum of the first 7 terms of this sequence?

Find the sum to n terms of the sequence 7,77,777,7777,…….