There will be a difference between the SC on the real test and the SC from the OG because the GMAT has evolved over the years (I.e. increased emphasis on meaning) and OG problems are "old", retired GMAT problems. The closest approximation you will find to questions on the real test is the from the questions you face in the GMATPrep practice exams.
Your challenges with RC are shared by many. Here is a recent post on improving RC ability - increasing-readioddng-comprehension-151911.html
. You can also search the forum for similar threads to get valuable insights.
Kyle Widdison | Manhattan GMAT Instructor | Utah
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