Step 1: Write the sequence from the given data and identify the first term in the sequence, call this number a.

Step 2: Calculate the common difference(d) of the sequence.

Step 3: Identify the number of terms (n).

             EXAMPLE: In A.P 2, 4, 6,..... find the sum of the first 10 terms. So take


Step 4: Plug the values of n, d, and a into the formula.

             [FORMULA: The formula for finding the sum of first n terms of an  

             arithmetic sequence (S_n) =(n/2)[2a + (n- 1)d]

Step 5: Simplify further..(Apply the BODMAS rules)