脱式计算,能简算的要简算.
0.125×0.25×32
1500-18×120÷25?????
×101-0.75
÷[×(0.4+)]
÷[(+)×].
网友回答
解:(1)0.125×0.25×32,
=0.125×0.25×4×8,
=0.125×8×(0.25×4),
=1×1,
=1;
(2)1500-18×120÷25,
=1500-86.4,
=1413.6;
(3)×101-0.75,
=0.75×101-0.75,
=(101-1)×0.75,
=100×0.75,
=75;
(4)÷[×(0.4+)],
=÷[×(+)],
=÷[×],
=÷,
=×,
=;
(5)÷[(+)×],
=÷[×],
=÷,
=×,
=3.
解析分析:(1)把32看作4×8,运用乘法交换律与结合律简算;(2)先算乘除,再算减法;(3)把分数改为小数0.75,运用乘法分配律简算;(4)(5)题先算小括号内的,再算中括号内的,最后算括号外的.
点评:此题考查了四则混合运算.注意运算顺序和运算法则,灵活运用所学的运算定律简便计算