R4RS 6.5.5  (max number ...)  ==>  number
            (min number ...)  ==>  number

These procedures return the maximum or minimum of their arguments.

(max 3 4)      ==>  4   ; exact
(min 3 4.1)    ==>  3.0 ; inexact

Note: If any argument is inexact, then the result will also be
inexact.
