It is 1.62 NOT 1.63 as many schools still teach.Most schools still teach you to always round 5 up but, while this is a simple rule to teach, it is not appropriate. Under this rule:• if the following digit is 0 you don't round;• if the following digit is 1, 2, 3 or 4 you round down; and• if the following digit is 5, 6, 7, 8 or 9 you round up.As a result you are more likely to round up than round down and that introduces an upward bias into your calculations.The IEEE (Institute of Electronic and Electrical Engineers) standard 754 is to round 5 up or down so that the new last digit is even. See link for more: //en.wikipedia.org/wiki/Rounding#Round_half_to_even