2004/2005×2003
=(1-1/2005)×2003
=2003-2003/2005
=2002又2/2005
2004/2005×2006
=2004/2005×(2005+1)
=2004+2004/2005
=2004又2004/2005
2004/2005×2003
=(1-1/2005)×2003
=2003-2003/2005
=2002又2/2005
2004/2005×2006
=2004/2005×(2005+1)
=2004+2004/2005
=2004又2004/2005