题目内容
神机妙算．
×
÷
÷
÷
(
-
)÷
(
+
)÷
．
| 5 |
| 9 |
| 3 |
| 4 |
| 5 |
| 12 |
| 9 |
| 10 |
| 2 |
| 5 |
| 3 |
| 8 |
(
| 3 |
| 4 |
| 5 |
| 7 |
| 1 |
| 56 |
(
| 26 |
| 35 |
| 13 |
| 14 |
| 13 |
| 14 |
分析：（1）（2）把除法改为乘法，约分计算；
（3）（4）把除法改为乘法，运用乘法分配律简算．
（3）（4）把除法改为乘法，运用乘法分配律简算．
解答：解：（1）
×
÷
=
×
×
=1
（2）
÷
÷
=
×
×
=6
（3）（
-
）÷
=（
-
）×56
=
×56-
×56
=42-40
=2
（4）（
+
）÷
=（
+
）×
=
×
+
×
=
+1
=1
．
| 5 |
| 9 |
| 3 |
| 4 |
| 5 |
| 12 |
=
| 5 |
| 9 |
| 3 |
| 4 |
| 12 |
| 5 |
=1
（2）
| 9 |
| 10 |
| 2 |
| 5 |
| 3 |
| 8 |
=
| 9 |
| 10 |
| 5 |
| 2 |
| 8 |
| 3 |
=6
（3）（
| 3 |
| 4 |
| 5 |
| 7 |
| 1 |
| 56 |
=（
| 3 |
| 4 |
| 5 |
| 7 |
=
| 3 |
| 4 |
| 5 |
| 7 |
=42-40
=2
（4）（
| 26 |
| 35 |
| 13 |
| 14 |
| 13 |
| 14 |
=（
| 26 |
| 35 |
| 13 |
| 14 |
| 14 |
| 13 |
=
| 26 |
| 35 |
| 14 |
| 13 |
| 13 |
| 14 |
| 14 |
| 13 |
=
| 4 |
| 5 |
=1
| 4 |
| 5 |
点评：完成本题要注意分析式中数据，运用合适的简便方法计算．
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