Should numbers in inline math equations be displayed using CM math font or Times?

I received a proof for a journal paper (IEEE) where some of the numbers in the inline equations of my manuscript were changed to Times font (font used for text in the template IEEEtran.cls) and some others were not changed to Times and left as CM math font (font used for math in IEEEtran). I would like to be consistent throughout the document and know which one to use. For example, should I use:

$x=1$ m


or

$x=$ 1 m


(where m is for meters)? Another example would be: $x=2y$ or $x=$ 2$y$?

-
The question is ill posed: you should not have any part of your document in Computer Modern, if your document font is Times. Say \usepackage{mathptmx} or, better if you have an up-to-date TeX distribution, \usepackage{newtxtext,newtxmath} and the problem will disappear. –  egreg Nov 28 '12 at 20:56
I am using the IEEEtran style and I think (perhaps I am wrong) that the text uses the Times font and I thought that the math font was CM math, but perhaps it's something else. What I mean by my question is: should the numbers in inline equations be displayed in math font or text font? I cannot add packages when I correct the proofs, but I can tell them to adjust the font to either style. –  user12876 Nov 28 '12 at 22:13
That's a definitely bad choice by the developers of IEEEtran.cls. It's simply absurd to have text in Times and math in Computer Modern. –  egreg Nov 28 '12 at 22:43
I totally agree. Since the difference is so apparent between Times and CM, I need to figure out which one to use for numbers and stick with it for the whole document. I think it would be simpler to use CM math for numbers in inline equations. –  user12876 Nov 28 '12 at 22:53

I strongly suggest you to use the siunitx package which will allow consistent typesetting of numbers & units.

\documentclass{article}
\usepackage{siunitx}

\begin{document}

\texttt{\textbackslash num\{\textless Zahl\textgreater\}} formats numbers

Example: \num{1234567890.123}

\texttt{\textbackslash si\{\textless unit\textgreater\}} formats units

Example: \si{\meter/\second^2}

\texttt{\textbackslash SI\{\textless number\textgreater\}\{\textless unit \textgreater\}} formats numbers with units

Example: \SI{1234567890.123}{\meter}

\texttt{\textbackslash numlist\{\textless number;number;number\textgreater\}} formats lists of numbers

Example: \numlist{10;20;30}

\texttt{\textbackslash SIlist\{\textless number;number;number\textgreater\}\{\textless unit\textgreater\}} formats lists of numbers with unit

Example: \SIlist{10;20;30}{\meter}

\texttt{\textbackslash SIrange\{\textless number\textgreater\}\{\textless number\textgreater\}\{\textless unit\textgreater\}} formats number ranges with unit

Example: \SIrange{10}{20}{\meter}

\end{document}


-
My concern is not that much about units, because it only appears once or twice in the whole paper (so I guess I can handle their typesetting manually), but more on the correct font to use for the numbers in inline equations. Also, I cannot add packages for the correction of the proof, but can only ask them to change specific things. –  user12876 Nov 28 '12 at 20:05
Then I would make all numbers be part of the equation: $x=1$ The unit needs to be in an upright font anyway, I would probably use then the font of the text. –  Uwe Ziegenhagen Nov 28 '12 at 20:12
This is also what I did in my manuscript, but for some reason, the editor changed some (but not all) of the inline equations to the format "$x=$ 1" and I just want to make sure which style would be best (consistency above all). –  user12876 Nov 28 '12 at 22:19