I have exactly the same problem!
I am a non-native Speaker from Germany. I need a minimum score of 500 for an MBA program at the University of Central Arkansas.
Before two weeks I took the GMAT online for the first time.
The verbal section was ok and I managed the tasks without problems. However, I experienced a rabbit punch in the quantitative section, which completely destroyed my target score.
I have neever seen such hard and silly tasks before the real exam! I thought that this could be a good signal for a high scoring range, because the quantitative tasks get never easier in the further test. This was a misjudgment!
I am now preparing for the GMAT since 10 weeks. At first, I started with some training in
the Official Guide 2020 (inclusive Reviews) and continued with the
Manhattan Prep Books. After finishing all the theoretical basics, I bought GMAT Official Practice Exams 3, 4, 5 & 6 and went on with these online tasks at mba.com.
Overall, I did all the 6 diagnostic test on mba.com
Let me add some results of the Diagnostic tests:
Quantative - score: from 42 to 49
Verbal - score from 25 to 30
To my math skills: In the last weeks, I got more and more confidence with the tasks and was able to manage medium and hard tasks without problems. But I never saw quant tasks in this way before. All in all, I was not able to find any calculation approach.
The only feasible explanation is that the algorithm does not work in my quant section, maybe because of techniqual issues. My study partner took the GMAT online to the same time and reported the same problem!
I will try now everything to come in contact with the customer service. But it is nearly impossible to get an answer!
Best regards
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