Hi ash4gmat,

One of the great aspects of the GMAT is that most questions can be approached in a variety of ways (so you won't necessarily get 'stuck' if one method doesn't help you to get the correct answer - you can try another). The OG books are great sources for practice questions, but they are NOT designed to teach you tactics, pattern-matching skills or the 'secrets' to the GMAT - the answer explanations often involve an overly 'technical' approach, which is what I think you're referring to when you refer to those solutions as 'unconvincing.'

Based on what you've written, I think that you would benefit a great deal from enrolling in a GMAT Course of some type (either Guided Self-Study or instructor-led).

1) What is your goal score?
2) What resources have you used so far during your studies?
3) When are you planning to take the GMAT?

GMAT assassins aren't born, they're made,
Rich

To find a solution do I need to ask a solution to each problem every time in BTG Forum or do we have any other options?Please suggest.

Almost every question from OG 2015 has probably been posted on BTG at least once. Type the question into google and you'll find several posts on BTG and other sites. However, posting your own specific question can be very helpful - an expert can address exactly what your misunderstanding was.

Manhattan Prep has answer explanations to the questions from OG 2015 (and OG 2016) on Navigator - the tool that tracks and analyzes your OG data. If you're interested, you can download Navigator here: https://www.manhattanprep.com/gmat/stor ... navigator/