The LaTeX calc package
Version: 5.5 - Scientific WorkPlace & Scientific Word
The calc package provides infix notation arithmetic, which is easier to use and modify and more readable than LaTeX commands. Infix expressions can be used in macro arguments. The package is used most often when creating typesetting specifications.
For more information, see the package documentation. The package is installed in the LaTeX/required/tools subdirectory as part of the Standard LaTeX Tools Bundle.