i need to know the formula on working out percentages of numbers!
You may find, say, Math on Call handyhttp://www.amazon.com/exec/obidos/tg/detail/-/0669457701/qid=1040484819/sr=1-1/ref=sr_1_1/002-0116185-4144809?v=glance&s=books
http://www.amazon.com/exec/obidos/tg/detail/-/0669457701/qid=1040484819/sr=1-1/ref=sr_1_1/002-0116185-4144809?v=glance&s=books