<H1>Practice in the sequences-puzzle 166-by Panos Kalliantasis</h1>

 A collection in number sequences

By Panos Kalliantasis

Math Puzzle 166 

One more exercise in series

Try to solve this math problem and check your answer.

The first 2-digit number is 12

and the last 2-digit number which disible by 3  is 99

It is an A.P difference =3

So 99=12+(n-1)*3  

n=30

Correct answer is C. 30