Finding the value of N (d1) and N (d2) on the standard distribution table

In open tuition lectures, we were instructed that when finding the value of either of the above mentioned variables, we first of all rought the answer off to two decimal places, as the table only accommodates up to two decimal places. However in the BPP revision Kit 2012, Question 32 bioplasm (12/03)-the model answer used an “adjusted method” of finding the values. It is nesessary to use this method, or can either methods work?

Thanks in Advance