计算:
①15.6789÷20÷5=________?
②34.5×8.23-34.5+2.77×34.5=________
③0.9999×0.7+0.1111×2.7=________.
网友回答
0.156789 345 0.9999
解析分析:①“连除”可转化成“除以这两个数的积”进行简便计算;
②可运用乘法分配律进行简便计算;
③可把“0.1111×2.7”转化成“0.9999×0.3”,再运用乘法分配律进行简便计算.
解答:①15.6789÷20÷5
=15.6789÷100
=0.156789;?
②34.5×8.23-34.5+2.77×34.5
=34.5×(8.23+2.77-1)
=34.5×10
=345;
③0.9999×0.7+0.1111×2.7
=0.9999×0.7+0.9999×0.3
=0.9999×(0.7+0.3)
=0.9999;
故