0.5 people or 0.5 person?

Hi,

When the number is less than one, whether it's expressed as a fraction or a decimal, you shouldn't use the plural form for that number. I think it's sort of a short-hand for 0.135 of an inch. So your plural is really in the 135 thousandths of an inch, not in the inch.

[Quoted from The Grammar Log ]

So, I gather that either 0.5 hour or half an hour is correct.

But which, 0.9 people or 0.9 person, should I put when I want to express a statistic?
0.9 people?/person? in the department suggest establishing a departmental library.

Given it is 0.5 people?/person?, I think half a person?/people? does not make sense. Right?

According Longman Dictionary of Contemporary English,
People is "used as the plural of 'person' to refer to men, women, and children."
[Quoted from http://www.ldoceonline.com/dictionary/people_1 ]

But after googling, I found both 0.9 people and 0.9 person are used. So both are okay?