Use of Plural with Decimal Numbers
Date: 02/27/2002 at 09:37:12 From: Eric Derobert Subject: Use of plural with decimal numbers Hello ! For natural numbers, the use of plural is of course easy : 0 point, 1 point, 2 points, 3 points... But what happens when using decimal numbers between 1 and 2 ? What are the rules for 1.0001, 1.1, 1.5 or 1.999 ? Should we write 1.0001, 1.1, 1.5, 1.999 point or 1.0001, 1.1, 1.5, 1.999 points ? Thank you !
Date: 02/27/2002 at 12:32:59 From: Doctor Peterson Subject: Re: Use of plural with decimal numbers Hi, Eric. I believe you are asking whether, in English, we treat various numbers as singular or plural. My understanding is that we consider ONLY the number 1 as singular; in particular, zero is a plural: we say "0 degrees" or "0 (no) apples," not "0 degree" or "0 apple." We do not use fractions as adjectives at all, but say "half (of) an apple" or "two thirds of a degree" with the fraction standing alone as a noun phrase, so it would not be quite accurate to say that a proper fraction is singular. With a mixed number, we tend to use a plural: "one and a half apples." Applying these ideas to decimals, I would say 0.5 apple (half an apple, five tenths of an apple) 0.9 apple 1.1 apples 1.5 apples In other words, anything greater than one can be taken as plural, as well as zero and possibly negative numbers. But in many cases the plural might be used with decimals smaller than 1; I have no strong objection to "0.5 meters". I have not found a reference to support any of my advice, which is based mostly on what feels right to me. - Doctor Peterson, The Math Forum http://mathforum.org/dr.math/
Date: 02/27/2002 at 13:09:41 From: Eric Derobert Subject: Use of plural with decimal numbers Dear Dr Peterson, In fact, I did some research from my 1st asking, and the rule appears to be different in English and in French (I am from France). In French the rule is to use plural for a noun when the number before is greater or equal to 2 (see this official reference from Quebec- Canada : http://www.olf.gouv.qc.ca/index.html?/sommaire.html ). From the Guide to Grammar and Writing http://webster.commnet.edu/grammar/numbers.htm I found a different rule : when the absolute value of a fractional or decimal expression is 1 or less, the word it modifies should be singular (that's exactly what you apply in your 4 apples examples). "When fractional or decimal expression are 1 or less, the word they modify should be singular: 0.7 meter, 0.22 cubic foot, 0.78 kilometer. Precede decimal fractions with a value less than one with a leading zero before the decimal point." But also, when you say that singular applies only to 1, the examples you propose seem very familiar : I've heard "0 degrees", and I've read "0.5 meters"... Apparently, the rules then depend on languages and uses... But perhaps, some official rule exists for English as a whole ? How interesting ! Kind regards. Eric
Date: 02/27/2002 at 14:31:13 From: Doctor Peterson Subject: Re: Use of plural with decimal numbers Hi, Eric. English (and especially American English) has no "official" rules for anything, though there are many "experts" who claim to give such rules. But with or without regulation, this is definitely a linguistic issue rather than one of mathematics or logic. Each language has a different set of rules for number as well as other aspects of grammar - for example, some languages have not only a singular and a plural, but a "dual" for exactly two, which would raise additional questions when applied to, say, 2.001. Different rules may be equally logical, and different languages may have different needs. Here is another reference I found (from Germany, but referring to English: Vocabulary Box: SI Units of Measure(ment) http://mueller.zems.tu-berlin.de/evti/students/unit1/voc/bx_SI.html With a few exceptions, plurals of spelled-out units are formed conventionally. Use the singular form with numbers less than or equal to 1, and use the plural form with numbers greater than 1. (In spoken English, however, decimal numbers take the plural form even if they are less than 1, e.g. "a quarter second" but "zero point two five seconds.") This shows that both of the rules I gave have their place. - Doctor Peterson, The Math Forum http://mathforum.org/dr.math/
Date: 02/27/2002 at 16:57:13 From: Doctor Peterson Subject: Re: Use of plural with decimal numbers Hello, Eric! I looked again and found that although your Quebec URL referred only to the main page (because the source uses a frame), another link takes me to a FAQ with the answer you described: http://www.olf.gouv.qc.ca/ressources/faq/760.html Here is a translation: Agreement of the noun after a fractional number less than two The noun that follows a fractional number less than two, such as one and a half, does not take the plural. Contrary to the English use, the name million, when one writes 1,5 million, remains in the singular. Moreover, the oral pronunciation shows that it is about a unit: one million five hundred thousand. The rule of agreement is the following: a name preceded by a number takes the plural only when this number is equal to or greater than two. Here are some examples: 1,3 billion people (it is necessary to say: a billion three hundred million people); 1,47 meter (it is necessary to say: one meter 47); An average of 1,25 child by household (it is necessary to say: a child and a quarter). Note that "the English use" for "million" differs from the American usage; the English say "1.5 millions," but we Americans use the singular no matter how many million it is. I suspect that the reason for the French rule lies in the way you say the number. You say the whole part, then the unit (million, meter, child), then the fractional part (three hundred million, 47, quarter). So if the whole part is one, you use the singular, and if it is two or more you use the plural. We think of the entire number as more than one and therefore plural; you use only the whole part as a direct modifier, which is NOT more than one in these cases, though a fraction is then added to it. The difference is entirely in the grammar, which determines the choice of words. Another page gives some related ideas on fractions: La foire aux questions linguistiques http://www.olf.gouv.qc.ca/ressources/faq/815.html In English we tend always to think of the fraction as a number in itself, rather than as a phrase, and to emphasize agreement in meaning rather than form; we would never say "2/3 of the road are open," even though grammatically the subject of the verb is the plural "thirds." But we would say "2/3 of the students are present," because there must be more than one student. On the other hand, the British would say "2/3 of the class are present," while an American might prefer "2/3 of the class is present," because we tend to treat collective nouns as singular. Language has its reasons, but they are not always in agreement. Of course, this is entirely a grammatical matter in French, and mostly a logical issue in English (that is, we aren't thinking of grammar, but only of whether more than one is under consideration). So in French this usage with fractions disagrees with the "two or more are plural" rule, because the grammar differs in the two cases, whereas in English we more consistently focus on the meaning. I've enjoyed looking into this issue, even though it is really a question for Dr. Linguistics. - Doctor Peterson, The Math Forum http://mathforum.org/dr.math/
Date: 02/28/2002 at 05:23:05 From: Eric Derobert Subject: Use of plural with decimal numbers Dear Dr Peterson, Thank you for spending such an amount of time to answer this paramathematical topic ! This is very complete. I think you are right when emphasizing the role of the way of saying numbers : "1.50 meters" in English and "1 metre 50" in French, which is written "1,50 metre" for consistency. Kind regards, and thank you again ! Eric
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