考點(diǎn):分?jǐn)?shù)的四則混合運(yùn)算
專(zhuān)題:運(yùn)算順序及法則
分析:(1)根據(jù)分?jǐn)?shù)減法的計(jì)算方法進(jìn)行計(jì)算;
(2)根據(jù)乘法分配律進(jìn)行簡(jiǎn)算;
(3)根據(jù)分?jǐn)?shù)加法的計(jì)算方法進(jìn)行計(jì)算
(4)根據(jù)小數(shù)除法的計(jì)算方法進(jìn)行計(jì)算;
(5)按照從左向右的順序進(jìn)行計(jì)算;
(6)根據(jù)減法的性質(zhì)進(jìn)行簡(jiǎn)算;
(7)根據(jù)乘法交換律和結(jié)合律進(jìn)行簡(jiǎn)算;
(8)先算除法和乘法,再算加法;
(9)根據(jù)減法的性質(zhì)進(jìn)行簡(jiǎn)算.
解答:
解:(1)
-
=
;
(2)(
+
-
)×30
=
×30+×30-
×30
=6+10-5
=16-5
=11;
(3)
+
=
;
(4)100÷0.01=10000;
(5)
×
×
=
×
=1;
(6)28-
-
=28-(
+
)
=28-1
=27;
(7)13×4÷13×4
=(13÷13)×(4×4)
=1×16
=16;
(8)2÷1
+2×
=
+
=
;
(9)6.54-2.8-1.2
=6.54-(2.8+1.2)
=6.54-4
=2.54.
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.