The toughest section in CAT and even a single mark or 2 can get you a 50 percentile. So that means out of 2 lac aspirants who give this exam, around 1 lac students aren't even able to get 3 marks(which is marks allocated for one question). Tens of thousands of students end up getting a negative score. But with proper planning and execution, you can score well in this section.
Now, the best preparation strategy would be to get used to doing the following steps:
Get your basics strong. Start solving all the basic LR and DI questions. Get comfortable with all the topics in the index(of any decent CAT DILR textbook)and although these basic questions may not be asked in the exam as such, but they may be the component of a question. Also get comfortable with all graphs and being able to convert one graph to another. By basics I mean:
LR: arrangements, selections, coding-decoding, etc.
DI: QA topics such as percentages, ratios, proportion and variation, and graphical topics like pie chart, bar chart, line graph, etc.
Start doing logical puzzles such as kakuro and sudoku. This helps your mind to develop critical thinking and it'll be a source of constant practice for it.
If you have you basics in place, it's time to up the game as in CAT they don't ask any question which is basic in nature. So to ace these you need to do questions of this level. A good source of these level questions would be previous year CAT questions and mocks from TIME/CL/IMS.
Talking about mocks, while taking the DILR section make sure you work on your strategy, you only need to solve 4~5 sets. So decide various things after giving many mocks to see which is working the most for you like how long you want to scan and how long you want to spend on a question and give up and so on to improve your decision making.
After mocks, solve the entire 8 sets and do the analysis thoroughly and look for the following details
Did you miss any easy set and if so why? Can you fix your strategy to avoid missing out on easy questions?
Did you solve a very hard set which wasn't worth it in terms of the time spent? Again analyse if you should have maybe left it in less time or if you shouldn't have selected it in first place.
Among the easy/medium sets, did you use the optimal method to solve the sets. Did you take the correct amount of time to solve it. For checking if your technique was good or not, you can compare it with solutions given by many of the coaching institutes.
Use your understandings from the analysis for the betterment of your strategy and to improve in the upcoming mocks.
Also, have a book where you jot down all your mistakes and learnings from the mocks you have given. Go through this before your next mock and make sure you don't repeat any mistakes.
One thing I did that helped me occasionally had DILR days, just like you have the leg days of gym. On this day I would have a marathon of DILR questions solving around 10 to 15 sets and analyse them in extreme detail to extract the maximum value.
Few tips for DILR would be:
Do scan briefly the whole paper as you do not want to miss out the sitters. If you check the last 6 papers in the last 3 years, DILR was the hardest section to score, but nevertheless there were always two sets that were very easy. So do not ever miss them out. Also just by looking at the sum, you can't tell if it's a sitter or not, you need to go through the details provided to make an informed decision if you want to attempt it right now (or later or skip it for good).
Don't solve based on LR or DI first even if it's your strength. Your strategy must be to find the 2/3 easiest sets and cracking them first.
Learn the concept of 'sunken cost'. Like for instance even if you have spent 10 mins and have not got anywhere and still have no idea on what approach you have to solve it, then it's better to leave it and move on.
Treat each section separately. Think of it as 3 one hour exams. Don't let your VARC affect your DILR performance and don't let your DILR affect you QA performance.
Even if your first 10–15 minutes are screwed up, it's fine to take a deep breath and understand it's a relative exam and go at it again. Even I didn't mark any question in the first 15 minutes of my CAT 19 exam, but in the remaining time I ended up scoring 50 marks even after marking 2 questions wrong after solving them correctly.
Also, it's not always a good idea to solve an entire set, few of the times 3 questions in a set may be easy, but the fourth question may be time taking, in which case it makes sense to move on to the next set(you can always come back if needed).
Leave a DI for the last preferably compared to an LR set. I say this as if you have solved a set and see that there are 4 minutes remaining, it may not be possible to solve an LR set, but in some DI sets, we can solve the questions independently.
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