@Maddus Mattus: And more importantly, treating a closeed-book exam as open-booked one won't gives you correct set of result (as you'll be assessing how well the candidate do when given books to "fill in the blanks". Remember, the questions in open-booked exam should be different from closed-book ones.).

So unless it's designed to be open book exam, calculators that can be used to cheat should not be allowed.