Ca final company law: retirement of directors by rotation

Hello, I am preparing for CA Final May 2017 for the first time-self study Haven't been to any coaching classes. I am strictly following ICAI Study Material and Practice Manual and not referring to any other Author Books. Re: Company Law-Retirement of Directors by Rotation. In the study Material it is given that out of 2/3rd, 1/3rd will retire and if it is a decimal Number then "Number nearest to 1/3rd shall Retire". Further an example is given that If 6 are Total No of Directors, 4 will be liable to retire, and out of 4, 4x1/3=1.33 will retire i.e Only one will retire. But in the practice Manual Q 5, Pg: 3.5, it is stated as 2 will retire. Which is Right. I am not clear about the phrase ""Number nearest to 1/3rd shall Retire"". Let me know what it means. Does it mean Rounding off to nearest Decimal or considering any fraction as 1. Thank You.