问题
解答题
用简便方法计算.
5.39+5.25+4.61+4.75
5.83-(0.46+1.83)-0.54.
答案
5.39+5.25+4.61+4.75
=(5.39+4.61)+(5.25+4.75),
=10+10,
=20;
5.83-(0.46+1.83)-0.54.
=5.83-0.46-1.83-0.54,
=5.83-1.83-(0.46+0.54),
=4-1,
=3.
用简便方法计算.
5.39+5.25+4.61+4.75
5.83-(0.46+1.83)-0.54.
5.39+5.25+4.61+4.75
=(5.39+4.61)+(5.25+4.75),
=10+10,
=20;
5.83-(0.46+1.83)-0.54.
=5.83-0.46-1.83-0.54,
=5.83-1.83-(0.46+0.54),
=4-1,
=3.