考點(diǎn):整數(shù)、分?jǐn)?shù)、小數(shù)、百分?jǐn)?shù)四則混合運(yùn)算,運(yùn)算定律與簡(jiǎn)便運(yùn)算
專題:運(yùn)算順序及法則,運(yùn)算定律及簡(jiǎn)算
分析:(1)先算乘法,再算減法;
(2)運(yùn)用乘法交換律與結(jié)合律簡(jiǎn)算;
(3)把16看作15+1,運(yùn)用乘法分配律簡(jiǎn)算;
(4)約分計(jì)算;
(5)(6)(7)運(yùn)用乘法分配律簡(jiǎn)算.
解答:
解:(1)
×
-
=
-
=0
(2)
×(8+15)×
=(
×
)×23
=
×23
=
(3)16×
=(15+1)×
=15×
+
=9+
=9
(4)0.3×
=0.2
(5)(
+
)×16
=
×16+
×16
=12+10
=22
(6)
×
+
×
=
×(
+
)
=
×1
=
(7)
×
+
×
+
=
×(
+
+1)
=
×2
=
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)算定律簡(jiǎn)便計(jì)算.