LAST EDITED ON Apr-02-02 AT 10:49 PM (EST)
http://www.cut-the-knot.com/cgi-bin/dcforum/ctk.cgi?az=show_thread&forum=DCForumID3&om=147&omm=0&viewmode=threadedOn that page, there's another discussion on that same problem. A link to mathsoft.com is broken, though, as they have recently changed the layout of their site. Try this:
http://www.mathcad.com/library/LibraryContent/puzzles/soln15/soln15.html