题目内容
(
+
+
+
)+(
+
+
+
)+(
+
+
)+(
+
)+
=
| 1 |
| 3 |
| 1 |
| 6 |
| 1 |
| 10 |
| 1 |
| 15 |
| 2 |
| 3 |
| 2 |
| 6 |
| 2 |
| 10 |
| 2 |
| 15 |
| 3 |
| 6 |
| 3 |
| 10 |
| 3 |
| 15 |
| 4 |
| 10 |
| 4 |
| 15 |
| 5 |
| 15 |
4
4
．分析：通过观察，发现此算式较长，通过变形，运用乘法分配律计算较简便．
解答：解：（
+
+
+
）+（
+
+
+
）+（
+
+
）+（
+
）+
，
=（
+
+
+
）+（
+
+
+
）×2+（
+
+
）×3+（
+
+
），
=（
+
+
+
）×3+（
+
+
）×3+1，
=（
+
+
+
）×3+1，
=（
+
+
）×6+1，
=
×6+1，
=3+1，
=4．
故答案为：4．
| 1 |
| 3 |
| 1 |
| 6 |
| 1 |
| 10 |
| 1 |
| 15 |
| 2 |
| 3 |
| 2 |
| 6 |
| 2 |
| 10 |
| 2 |
| 15 |
| 3 |
| 6 |
| 3 |
| 10 |
| 3 |
| 15 |
| 4 |
| 10 |
| 4 |
| 15 |
| 5 |
| 15 |
=（
| 1 |
| 3 |
| 1 |
| 6 |
| 1 |
| 10 |
| 1 |
| 15 |
| 1 |
| 3 |
| 1 |
| 6 |
| 1 |
| 10 |
| 1 |
| 15 |
| 1 |
| 6 |
| 1 |
| 10 |
| 1 |
| 15 |
| 12 |
| 30 |
| 8 |
| 30 |
| 10 |
| 30 |
=（
| 1 |
| 3 |
| 1 |
| 6 |
| 1 |
| 10 |
| 1 |
| 15 |
| 1 |
| 6 |
| 1 |
| 10 |
| 1 |
| 15 |
=（
| 1 |
| 3 |
| 1 |
| 3 |
| 2 |
| 10 |
| 2 |
| 15 |
=（
| 1 |
| 3 |
| 1 |
| 10 |
| 1 |
| 15 |
=
| 1 |
| 2 |
=3+1，
=4．
故答案为：4．
点评：凡是简算的题目，首先应仔细观察，发现特点或规律，运用已学知识进行简便计算．
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