What is standard numerical tests for IT graduates


I am going for number of IT graduates scheme at all the IT companies such as logica, ibm atos orgin and so on. I have read number of posts on this forum stating that it is a standard numerical test which can be found on such places as assessmentday.co.uk. I have purchased these numerical test from that website and some are easy while others are little difficult. How would you describe what is standard numerical tests? Would you say all the numerical test questions from assessmentday are standard?..MrR.