题目内容
1+2
+3
+4
+5
+6
+7
+8
+9
+10
=______.
| 1 |
| 6 |
| 1 |
| 12 |
| 1 |
| 20 |
| 1 |
| 30 |
| 1 |
| 42 |
| 1 |
| 56 |
| 1 |
| 72 |
| 1 |
| 90 |
| 1 |
| 110 |
1+2
+3
+4
+5
+6
+7
+8
+9
+10
,
=(1+2+3+4+5+6+7+8+9+10)+(
+
+
+
+
+
+
+
+
),
=(1+10)×10÷2+(
-
+
-
+…+
-
),
=55+(
-
),
=55+
,
=55
.
故答案为:55
.
| 1 |
| 6 |
| 1 |
| 12 |
| 1 |
| 20 |
| 1 |
| 30 |
| 1 |
| 42 |
| 1 |
| 56 |
| 1 |
| 72 |
| 1 |
| 90 |
| 1 |
| 110 |
=(1+2+3+4+5+6+7+8+9+10)+(
| 1 |
| 6 |
| 1 |
| 12 |
| 1 |
| 20 |
| 1 |
| 30 |
| 1 |
| 42 |
| 1 |
| 56 |
| 1 |
| 72 |
| 1 |
| 90 |
| 1 |
| 110 |
=(1+10)×10÷2+(
| 1 |
| 2 |
| 1 |
| 3 |
| 1 |
| 3 |
| 1 |
| 4 |
| 1 |
| 10 |
| 1 |
| 11 |
=55+(
| 1 |
| 2 |
| 1 |
| 11 |
=55+
| 9 |
| 22 |
=55
| 9 |
| 22 |
故答案为:55
| 9 |
| 22 |
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