Hi Ashok,

I can help get you started.

In an arithmetic progression (a.p.) there is a number called the common difference which is usually denoted $d.$ In an a.p. to get from any term to the next term you add the common difference. Thus, for example if an a.p. has a common difference od $d = 3$ and 5 is one of the terms then the next term is $5 + d = 5 + 3 = 8$ and the term after that is $8 + 3 = 11,$ and so on.

How many times do you add $d$ to get from the 4th term to the 10th term? What is the difference between the 4th term and the 10th term of your sequence? What is $d?$

Penny