考點(diǎn):整數(shù)、分?jǐn)?shù)、小數(shù)、百分?jǐn)?shù)四則混合運(yùn)算,整數(shù)四則混合運(yùn)算,運(yùn)算定律與簡(jiǎn)便運(yùn)算,小數(shù)四則混合運(yùn)算
專題:運(yùn)算順序及法則,運(yùn)算定律及簡(jiǎn)算
分析:①運(yùn)用乘法的結(jié)合律進(jìn)行計(jì)算即可.
②把40%化成分?jǐn)?shù)
,然后運(yùn)用乘法的分配律進(jìn)行計(jì)算即可.
③④根據(jù)四則混合運(yùn)算的順序進(jìn)行計(jì)算即可.
解答:
解:①12.5×
×3.2×25
=12.5×(
×3.2)×25
=12.5×0.8×25
=10×25
=250
②
×
+40%×
=
×
+
×
=
×(
+
)
=
③375+450÷18×25
=375+25×25
=375+625
=1000
④13.6-(2.6+0.25÷25%)
=13.6-(2.6+0.25÷0.25)
=13.6-(2.6+1)
=13.6-3.6
=10
點(diǎn)評(píng):考查了運(yùn)算定律與簡(jiǎn)便運(yùn)算,四則混合運(yùn)算.注意運(yùn)算順序和運(yùn)算法則,靈活運(yùn)用所學(xué)的運(yùn)算律簡(jiǎn)便計(jì)算.