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Units of length

ValeryOchkov
24-Ruby IV

Units of length

Why is there a minus sign and not a plus sign.
I heard that this is some kind of military secret of the British - the enemy did not know the true height of the soldiers! 

And more: F - feet, I - inch, F - ? Fraction?

FIF.png 

 

 

6 REPLIES 6


@ValeryOchkov wrote:

Why is there a minus sign and not a plus sign.
I heard that this is some kind of military secret of the British - the enemy did not know the true height of the soldiers! 


If I told you, Valery, I'd have to shoot you. 😈

 

Why is there a minus sign and not a plus sign.
And more: F - feet, I - inch, F - ? Fraction?

FIF.png 

 

 


Yes, Feet, Inches Fractions.

 

The dash (not minus sign) is, думаю, an old convention to show that the fraction relates to the inches.  However, there should be space there, instead.  Furthermore, 127 should not appear as a fraction - fractions are conventionally written as nearest reciprocal powers of 2 (or 3 or 10, but certainly not 127 for general use!).

 

Oh dear.  I've told you ... <sigh> I guess I'll let you off this time, but don't think this sets a precedent.

 

Anyway, needless to say, the real crime and abomination here is those quote marks around the numeric value!! 👿

 

What is it with PTC and all these string-surrounding quote marks?  Did they overstock them and are now trying to dump them on innocent Mathcad users?

 

Stuart

 

https://www.nist.gov/system/files/documents/2017/04/28/AppB-12-hb44-final.pdf

 

https://www.nist.gov/system/files/documents/2017/05/09/13-section-IVa-14-h130-final.pdf

 

6.11. Fractions.
(a) Inch-pound: An inch-pound statement of net quantity of contents of any consumer commodity may
contain common or decimal fractions. A common fraction shall be in terms of halves, quarters, eighths,
sixteenths, or thirty-seconds, except that:
(1) if there exists a firmly established general consumer usage and trade custom of employing different
common fractions in the net quantity declaration of a particular commodity, they may be employed;
and
(2) if linear measurements are required in terms of yards or feet, common fractions may be in terms of
thirds.

Why not

OZF.png


@ValeryOchkov wrote:

Why not

OZF.png


Because

 

a. The mixed number format is incorrect (no dash, just a thin space). 

 

b. Nobody in their right mind would give ounces to such precision when 10/49 or 1/5 would be quite adequate (except, of course, a mathematician giving advice to aeronauts in a passing balloon. 😉)

 

c. The double use of 'oz' makes it look like the faction is being subtracted; there should only be one 'oz' because 13.204 oz should be represented as a mixed number (standards, and all that).

 

d. It would confuse Army caterers, who would, in turn, annoy the Army engineers tasked to build kitchen scales of such accuracy and precision.

 

e. The quotes, the quotes ...

 

Stuart

In Russia, in such cases, we say that all ancient Greek mathematicians turned over in their graves. And what do they say in England in such cases?

PiFraction.png


@ValeryOchkov wrote:

In Russia, in such cases, we say that all ancient Greek mathematicians turned over in their graves. And what do they say in England in such cases?


We'd say something similar in the United Kingdom (*).

 

PiFraction.png


Are you telling me that those weights are from the recipe for a πie from a mathematician's cookbook?  Raspberry?

 

Stuart

 

(*) many people from Wales, Scotland, Northern Ireland, etc can get a bit touchy when people confuse being England with Great Britain, and being English with being British

 

 

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