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Naming Large Numbers

Date: 06/05/2002 at 18:46:40
From: Joey
Subject: large number naming

If 100 is hecto-, then would 110 be hectodeca-?  In short, is this the
correct way of putting them together?
       100,000 - hectochilia-
     1,000,000 - hectomyria- 
    10,000,000 - decahectomyria- 
   100,000,000 - decachiliamyria- 

and then from Russ Rowlett's page: 

 1,000,000,000 = gillion. 

Is the prefix "giga" Greek or Latin? 

In Rowlett's site, he says 

  trillion (American) = tetrillion (Greek)
But tetra is 4. And trillion is 3. So, he's saying, 3 = 4. Same for 
quadrillion, which in Greek, is pentillion. 

Why doesn't he just call quadrillion, tetrillion? It's like for every
American number, he bumps the prefix up one number in the Greek-based
names, ya know? 


Date: 06/05/2002 at 22:59:04
From: Doctor Peterson
Subject: Re: large number naming

Hi, Joey.

I suppose you should be asking Mr. Rowlett himself; I can only guess 
how he would expand on his ideas. But I think I understand what he is 
doing well enough.

You are referring to 

In your discussion of hecto- and so on, it is not clear what your 
context is; you are building either Greek-based prefixes such as 
would be used for polygons (see our FAQ page on that), or pseudo-
metric prefixes, neither of which would be done quite as you suggest, 
and neither of which is related to building names for numbers. 
Gillion isn't a prefix; and Rowlett doesn't use metric prefixes in 
his proposed system.

The metric prefixes come from various sources; "giga-" is from Greek, 
as in "gigantic" -- not strictly a number prefix, but just one of a 
series of names that mean "huge" or "tiny". See this page for details: 

This is the only metric prefix Rowlett uses, and it is used only to 
avoid having to use "billion" for the American billion and confuse 
Europeans. It's a compromise that doesn't quite fit his scheme.

Rowlett's scheme for naming numbers is intended to deal with the 
problems of both the American and the European systems. The latter 
has the advantage of being proportional: a billion has twice as many 
zeros as a million, and so on, so the number of zeros is proportional 
to the number prefix, which is not true of the American system. But 
it has the disadvantage of a large granularity: only powers of a 
million get special names, so there is no easy way to say 
1,000,000,000, which is called "thousand million". 

Rowlett's scheme is a proportional naming system, but is based on
thousands rather than millions, so it differs from the American scheme
only in being proportional, and from the European in its granularity.
After thousand, million, and gillion, which have 1, 2, and 3 groups of 
three zeros and do not have numeric prefixes, the numeric prefix 
corresponds exactly to the number of groups. That is why the 
numbering is off by one compared to the American numbers: the 
American sytem is off by one, and he is fixing that. If he just 
translated Latin to Greek, what would be the point?

Incidentally, 10^300 would be a hectillion in his system.

- Doctor Peterson, The Math Forum 
Associated Topics:
Elementary Large Numbers
Elementary Math History/Biography
Elementary Number Sense/About Numbers
Middle School History/Biography
Middle School Number Sense/About Numbers

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