题目内容
| 29 |
| 42 |
| 27 |
| 56 |
| 41 |
| 72 |
| 85 |
| 99 |
| 107 |
| 143 |
| 177 |
| 182 |
分析:通过观察,每个分数的分母可以拆成两个数的乘积,再把每个分数拆成两个分数相减的形式,但要注意99和143拆成的是两个连续的奇数,相差2,所以应乘
.然后通过计算得出结果.
| 1 |
| 2 |
解答:解:
+
+
+
+
+
,
=(
-
)+(
-
)+(
-
)+(
-
)+(
-
)+(
-
),
=(4
-4
)+(3
-3
)+(4
-4
)+(3
-3
)+(4
-4
)+(12
-12
),
=
-
+
-
+
-
+
-
+
-
+
-
,
=
+
+
+
+
-
,
=
+(
-
)+
+
+
,
=(
+
)+
+(
+
+
)
=2+
+
,
=5
.
| 29 |
| 42 |
| 27 |
| 56 |
| 41 |
| 72 |
| 85 |
| 99 |
| 107 |
| 143 |
| 177 |
| 182 |
=(
| 29 |
| 6 |
| 29 |
| 7 |
| 27 |
| 7 |
| 27 |
| 8 |
| 41 |
| 8 |
| 41 |
| 9 |
| 42.5 |
| 9 |
| 42.5 |
| 11 |
| 53.5 |
| 11 |
| 53.5 |
| 13 |
| 177 |
| 13 |
| 177 |
| 14 |
=(4
| 5 |
| 6 |
| 1 |
| 7 |
| 6 |
| 7 |
| 3 |
| 8 |
| 9 |
| 8 |
| 5 |
| 9 |
| 15.5 |
| 9 |
| 9.5 |
| 11 |
| 9.5 |
| 11 |
| 1.5 |
| 13 |
| 21 |
| 13 |
| 9 |
| 14 |
=
| 5 |
| 6 |
| 1 |
| 7 |
| 6 |
| 7 |
| 3 |
| 8 |
| 9 |
| 8 |
| 5 |
| 9 |
| 15.5 |
| 9 |
| 9.5 |
| 11 |
| 9.5 |
| 11 |
| 1.5 |
| 13 |
| 21 |
| 13 |
| 9 |
| 14 |
=
| 5 |
| 6 |
| 5 |
| 7 |
| 3 |
| 4 |
| 10.5 |
| 9 |
| 19.5 |
| 13 |
| 9 |
| 14 |
=
| 5 |
| 6 |
| 10 |
| 14 |
| 9 |
| 14 |
| 3 |
| 4 |
| 7 |
| 6 |
| 3 |
| 2 |
=(
| 5 |
| 6 |
| 7 |
| 6 |
| 1 |
| 14 |
| 3 |
| 4 |
| 7 |
| 6 |
| 3 |
| 2 |
=2+
| 1 |
| 14 |
| 41 |
| 12 |
=5
| 1 |
| 2 |
点评:此题计算量较大,需仔细谨慎,切忌浮躁,做到思路清晰,循序渐进,得出结果.
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