Error rate on SC? That really doesn't matter when it comes to scoring in 700+ range.
It's not how many questions you get right vs wrong, it's really which level of questions you get it right consistently.
If your verbal weakness is SC - then practice from easier SC questions to mid level difficulty SC questions - to finally very difficult SC questions.
The idea is to master easier (level wise) SC questions right consistently so the CAt exam will show you next level (in difficulty) questions. If you get mid level SC questions correct consistently, then CAT will show you very difficult SC questions. However, the actual CAt exam will mix SC, RC, CR questions.
So make sure you get all the fundamentals right for all types of verbal questions and practice a lot before the exam.
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