The math is just mental arithmatic if you know your times tables you will be fine just work out the problems as basic equations and you will finnish them all with time to spare to double check them. remember you do not need to work out the answer to the decimal all you need to do is have a rough idea what the answer should be as you are given 5 choices. eg if you were asked whats 101/5 you do not need to know its 20.2 you should know straight away its just over 20 and the 20.2 anwer will be staring you in the face. hope this helps
cheers