能简便计算的要简算
5×0.125×16
(-÷4)×
8.5×+7.5×75%80%×45-60%÷ ÷[(-)×]÷[(+)-].
网友回答
解:(1)5×0.125×16,
=5×0.125×2×8,
=(5×2)×(0.125×8),
=10×1,
=10;
(2)(-÷4)×,
=(-)×,
=×,
=;
(3)8.5×+7.5×75%,
=8.5×75%+7.5×75%,
=(8.5+7.5)×75%,
=16×75%,
=12;
(4)80%×45-60%÷,
=80%×45-60%×45,
=(80%-60%)×45,
=20%×45,
=9;
(5)÷[(-)×],
=÷[×],
=÷,
=;
(6)÷[(+)-],
=÷[(-],
=÷,
=.
解析分析:(1)先把16分解成2×8,再运用乘法结合律简算;(3)(4)运用乘法分配律简算;其它题目按照先算乘除,再算加减,有括号的先算括号里面的顺序计算.
点评:运算定律是常用的简算方法,要熟练掌握,灵活运用.