题目内容
(2012?石阡县模拟)脱式计算(能简算的要简算)
41×101=
12×(
+
-
)=
5×
×
×
=
;
8.5-(5.6+4.8)÷1.3=
375+450÷18×25=
(
+
)÷
+
=
.
41×101=
4141
4141
;12×(
| 1 |
| 4 |
| 1 |
| 6 |
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| 3 |
1
1
;5×
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| 3 |
| 2 |
| 5 |
| 3 |
| 10 |
| 1 |
| 5 |
| 1 |
| 5 |
8.5-(5.6+4.8)÷1.3=
0.5
0.5
;375+450÷18×25=
1000
1000
;(
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| 5 |
| 1 |
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| 7 |
| 3 |
| 7 |
| 10 |
| 23 |
| 20 |
| 23 |
| 20 |
分析:(1)可将101拆分为100+1后根据乘法分配律计算;
(2)可根据乘法分配律计算;
(3)可通过约分简算;
(4)(5)(6)根据四则混合运算的运算顺序计算即可:先算乘除,再算加减,有括号的要先算括号里面的.
(2)可根据乘法分配律计算;
(3)可通过约分简算;
(4)(5)(6)根据四则混合运算的运算顺序计算即可:先算乘除,再算加减,有括号的要先算括号里面的.
解答:解:(1)41×101
=41×(100+1),
=41×100+41×1,
=4100+41,
=4141;
(2))12×(
+
-
)
=12×
+12×
-12×
,
=3+2-4,
=1;
(3)5×
×
×
=
;
(4)8.5-(5.6+4.8)÷1.3
=8.5-10.4÷1.3,
=8.5-8,
=0.5;
(5)375+450÷18×25
=375+25×25,
=375+625,
=1000;
(6)(
+
)÷
+
=
×
+
,
=
+
,
=
.
故答案为:4141,1,
,0.5,1000,
.
=41×(100+1),
=41×100+41×1,
=4100+41,
=4141;
(2))12×(
| 1 |
| 4 |
| 1 |
| 6 |
| 1 |
| 3 |
=12×
| 1 |
| 4 |
| 1 |
| 6 |
| 1 |
| 3 |
=3+2-4,
=1;
(3)5×
| 1 |
| 3 |
| 2 |
| 5 |
| 3 |
| 10 |
| 1 |
| 5 |
(4)8.5-(5.6+4.8)÷1.3
=8.5-10.4÷1.3,
=8.5-8,
=0.5;
(5)375+450÷18×25
=375+25×25,
=375+625,
=1000;
(6)(
| 4 |
| 5 |
| 1 |
| 4 |
| 7 |
| 3 |
| 7 |
| 10 |
=
| 21 |
| 20 |
| 3 |
| 7 |
| 7 |
| 10 |
=
| 9 |
| 20 |
| 7 |
| 10 |
=
| 23 |
| 20 |
故答案为:4141,1,
| 1 |
| 5 |
| 23 |
| 20 |
点评:完成有关于分数的计算时,要注意通分、约分,完成有关于小数的计算时,要注意小数点位置的变化.
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