题目内容
下面各题,怎样筒便就怎样算.
18÷(4.49+34.3×0.2) |
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(9-3.06÷
|
[1-(
|
考点:分数的四则混合运算,整数、分数、小数、百分数四则混合运算
专题:运算顺序及法则
分析:(1)先算乘法,再算加法,最后算除法;
(2)根据乘法分配律进行简算;
(3)根据加法交换律和结合律以及减法的性质进行简算;
(4)根据乘法分配律进行简算;
(5)先算除法,再算减法,最后算乘法;
(6)先算小括号里面的减法,再算除法,再算中括号里面的减法,最后算乘法.
(2)根据乘法分配律进行简算;
(3)根据加法交换律和结合律以及减法的性质进行简算;
(4)根据乘法分配律进行简算;
(5)先算除法,再算减法,最后算乘法;
(6)先算小括号里面的减法,再算除法,再算中括号里面的减法,最后算乘法.
解答:
解:(1)18÷(4.49+34.3×0.2)
=18÷(4.49+6.86)
=18÷11.35
=1
;
(2)
÷7+
×
=
×
+
×
=(
+
)×
=1×
=
;
(3)
-
-
+
=(
+
)-(
+
)
=2-1
=1;
(4)
×3.2+5.6×0.5+1.2×50%
=0.5×3.2+5.6×0.5+1.2×0.5
=(3.2+5.6+1.2)×0.5
=10×0.5
=5;
(5)(9-3.06÷
)×
=(9-5.1)×
=3.9×
=6;
(6)[1-(
-1.5)÷
]×0.75
=[1-
÷
]×0.75
=[1-
]×0.75
=
×0.75
=
.
=18÷(4.49+6.86)
=18÷11.35
=1
133 |
227 |
(2)
8 |
13 |
1 |
7 |
5 |
13 |
=
8 |
13 |
1 |
7 |
1 |
7 |
5 |
13 |
=(
8 |
13 |
5 |
13 |
1 |
7 |
=1×
1 |
7 |
=
1 |
7 |
(3)
11 |
10 |
1 |
4 |
3 |
4 |
9 |
10 |
=(
11 |
10 |
9 |
10 |
1 |
4 |
3 |
4 |
=2-1
=1;
(4)
1 |
2 |
=0.5×3.2+5.6×0.5+1.2×0.5
=(3.2+5.6+1.2)×0.5
=10×0.5
=5;
(5)(9-3.06÷
3 |
5 |
20 |
13 |
=(9-5.1)×
20 |
13 |
=3.9×
20 |
13 |
=6;
(6)[1-(
5 |
3 |
5 |
12 |
=[1-
1 |
6 |
5 |
12 |
=[1-
2 |
5 |
=
3 |
5 |
=
9 |
20 |
点评:考查了运算定律与简便运算,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.
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