In general, you're right that usually you would use the singular form for a decimal amount less than one:
0.1 acre = 0.1 of an acre = 1/10th of one acre
An exception is zero, which would usually be plural, as in 0 acres.
However, there's no definitive rule on this for English grammar, and some people would say that anything other than exactly 1 is plural:
0.9 acres, 1.1 acres, 0 acres, 1 acre
Also, if you use an abbreviation, the plural is the same as the singular:
0.9 ft, 1.1 ft, 0 ft, 1 ft
So I guess the answer is that if you follow most style guides, you would use the singular form if the amount is less than one. However, mainstream usage includes both versions so there isn't a definitive rule that everyone follows.
|01/30/2012, 4:41 PM||Less than One: Unit Measurements Singular or Plura...|
|01/30/2012, 5:51 PM||Re: Less than One: Unit Measurements Singular or P...|
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