You are not alone. Many people find that when they go off to study areas of weakness they tend to improve on those areas but at the same time their performance drops in former areas of strength. For most students the solution is surprisingly easy - consistently practice random GMAT problems in "Timed Sets" so you measure/maintain your performance on all GMAT content areas.
If you plan on studying 1:30 each day, I would recommend you spend 2/3 of that time on focused work (ie your planned CR review) and 1/3 of the time completing Official Guide practice. Take 10-20 minutes to work through 5-10 problems. Spend the rest of the time reviewing your work heavily - both the questions you got wrong and those you got right. This type of practice will help keep you sharp in all areas and reveal areas of weakness. As you get closer to test day, you should probably shift to spend 2/3 of your time on timed sets/review. If you find yourself hurting for study time, try to sneak that 30 minutes into some other part of your day, maybe your lunch break.
Kyle Widdison | Manhattan GMAT Instructor | Utah
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