(-7.25)+(-6.71)+(+4.25)+(-2.29);
问题描述:
(-7.25)+(-6.71)+(+4.25)+(-2.29);
1999+(-2001)+2002+(-2003)+2004+(-2005)
答
(-7.25)+(-6.71)+(+4.25)+(-2.29)
=-7.25+4.25-(6.71+2.29)
=-3-9
=-12
1999+(-2001)+2002+(-2003)+2004+(-2005)
=(1999-2001)+(2002-2003)+(2004-2005)
=-2-1-1
=-4