Q&A #7370

Teachers' Lounge Discussion: Use of commas in math

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From: Daniel Marr

To: Teacher2Teacher Public Discussion
Date: 2002092309:04:58
Subject: Re: use of commas in math - you bet!!

In response to Mr. Potter's opinions,

Maybe there are a lot of better reasons for using the commas in math.

You say, 

"It does more harm than good because children (and adults)
often have poor penmanship. So that 32,785,121.056 may look more like

So why don't we eliminate or revise the '1' because it often looks
like a '7' or the '8' for a '3', or vise-a-versa?   Let's go further.
why not revise the shape of the letters o, l, u because they sometimes
look like a, e, v respectively. Heck, why not eliminate the comma in
grammar, and the semicolon to boot.  Better yet, why not just improve
our penmanship. But then we would have to teach them how to hold a
pencil – WOW.– isn’t that part of the 3 R’s. Hold it. That could also
lead to teaching the correct use of cutlery. What will the world come
to. (Sorry for the dangling infinitive)

“…we don't use commas after the decimal point.  Why not?  There is no
good reason that commas should be limited to the left side of the
decimal point.”

Wrong! We use the comma to the left side of decimal point to help
grasp at a glance and reflect the way we read numerical values. One
comma denotes – ‘thousands’, two commas -‘millions, three – billions,
etc. For the right side we read each number individually. The KISS
principle at its best.

“I tell my students that commas are just a tradition and that most
people don't use them

Not in this neck of the woods. Interesting that one of the concerns
being expressed today is that the education system is not preparing
our kids to enter the work force. So why don’t we just ask your
banker, your accountant, the IRS, or the New York Stock Exchange,
whether they would advice you to or even let you write a check with
‘missing’ spaces, or post your sales, do your income taxes and print
your annual report without commas. Certainly it is recognized that it
is clearer and perhaps, it is simply that commas could also help
curtail fraudulent efforts to slip in another number between the empty

“So I would encourage them not to use them, but I don't mind either
way.  My alternative is what I was taught.”

My apologies. It’s your teachers I should be addressing.

“Rather than put a comma, just leave a space, it is not confusing…”

Simple rule again. One comma = thousands. Two = millions, etc.

“…and it is easier on the eyes.” 

Hold it! The use of spaces in lieu of commas is not a ‘mathematical
standard’. It is a ‘scientific COPY* standard’ used to address the
concerns of scientists who publish their documentation for
international audiences. We don’t, others do. Let’s make it easy. Take
them out. It’s printed; so not to worry about somebody attempting to
insert the odd number or two.

More important, the ‘scientific copy standard’ for writing numbers
between 1,000 and 9,999 is ‘NO SPACE’, e.g., is written 1000 and 9999
NOT ‘1 000 or 9 000’. So when it comes to writing up tables it can
look pretty ugly; better to put back the comma.

So you tell me, what is easier to write, read and add up? Forty-four
thousand, two hundred and seventy-six, plus one thousand, six hundred
and eighty-nine, plus five million, seven hundred and twenty-eight,
plus two thousand, one hundred and eleven; your way or the right way?
A little more difficult when they don’t line up.

Better yet. Who decided to adopt this non-comma standard? And when?
What law has been put in effect that everyone must adopt this
standard? Which agency? What law body. When must the business
community to comply? – Not in this neck of the woods!

Or perhaps it was just some computer geek that needed space on his
hard drive. (It must have been a man. Women are just more logical) Or
it was just faster to use the space bar than to hunt and peck for the
comma. Ah! There it is. But it is a bit too close to the period–best
to leave it out. It’s less confusing. (Probably the only time he used
more than his two index fingers to type).

Or perhaps, it was the new business paradigm that was being touted by
those wonder dot com founders. I’ll bet ENRON used it. Maybe if they
had kept the comma, they would have paused and thought about it for a
little while longer; and we wouldn’t be sitting around now with all
those empty spaces.

That’s just my BIG DIFFERENCE of opinion. 

Daniel Marr

*Operative word: 

Scientific Copy Standard Ref: 
The Chicago Manual of Style. Rev. ed of A manual of style.
12thed.rev.c1969: University of Chicago Press, 1982

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