VMS Help PASCAL, Predeclared Routines, Arithmetic, MAX  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  The MAX function returns a value (the same type as that  of  the
  parameters)  that  is  the  maximum value of a specified list of
  parameters.

  Syntax:

     MAX( x1,...,xn )

  The parameters can be any arithmetic type, but must  all  be  of
  the same type.