No Hamster you never get to use a calculator in a numerical reasoning test.
The reason for the test is because vast numbers of people just can't do numbers in their head. Haven't a clue how to divide and only know how to spell fraction. And time and motion is only to do with having a dump.
I will admit most of them will have better spelling and grammar than me. But as yet no plane has crash due to either of those traits. Quite a few though have crashed because some person hasn't managed to spot a gross error of over 10 tons on a load sheet due to a failure to carry a 1.