用你喜欢的方法计算下列各题. 12.06-0.5+0.5×0.27.4+0.38+0.22+2.6.
网友回答
解:(1)12.06-0.5+0.5×0.2,
=12.06-0.5+0.1,
=12.02;
(2)7.4+0.38+0.22+2.6,
=(7.4+2.6)+(0.38+0.22),
=10+0.6,
=10.6;
(3)(+)×45,
=×45+×45,
=30+6,
=36;
(4)350÷-350×,
=350×-350×,
=350×(-),
=350×,
=140.
解析分析:(1)先算乘法,再算加法和减法;(2)运用加法交换律与结合律简算;(3)运用乘法分配律简算;(4)把除法给位乘法,运用乘法分配律简算.
点评:考查了小数、分数的四则混合运算,注意运算顺序和运算法则,灵活运用所学的运算律简便计算.