Just finished taking the core and turf tests today, the core was 89 questions and the turf was 50 questions. Some of the questions were tough and confusing and others were just common sense. Took me just under two hours to complete them and I was taking my time re-reading each question carefully. Just like the other person said study as much as you can from the study guides they have the info you need. As far as needing a calculator if you're alright with simple multiplication and addition/subtraction you shouldnt need one but it could save you a few minutes.