1994+1996+1998+2000+2002+2004+2006分之1993+1995+1997+1999+2001+2003+2005
=1-(1994+1996+1998+2000+2002+2004+2006分之1+1+1+1+1+1+1)
=1-[(2000-6)+(2000-4)+(2000-2)+(2000)+(2000+2)+(2000+4)+(2000+6)分之7]
=1-[(2000X7)分之7]
=1-[2000分之1]
=1999/2000