I flew for them as a captain for four years, during which time I never failed a sim check, or had any arguments with management, and had no problem taking one of their aircraft over pretty much all of their routes from Norway and Finland to Greece and the Canaries.
I didn't have a clue what was happening in the on line maths test. It was all to do with production of clothing in a factory in Argentina or some such rubbish, all statistics.
With one minute before the end of the test I just randomly ticked answers for the last fifteen questions and presumably passed it as they interviewed me and gave me a job.
So, mathematical ability - pretty much zero. Ability to be a DEC with Jet2 - OK.
Was the test a waste of time? Yes.