The tests that leave you short of time are not designed to be completed in the time limit. Sure, some people may well complete them, but very few will (and even fewer people will get 100% - if any ever will). What they really want to see is your ability to accurately perform calculations under pressure. What they definitely don't want to see is you guessing your way through question after question and only scoring 25%. If you do this then you
will fail. Far better to answer 50% of the questions with 80% accuracy than 100% of the questions with 40% accuracy.
Hope it's helpful!
