分析:同分母分数相加减,分母不变,分子相加减;异分母分数相加减,先通分,化成同分母分数再计算.解答:解:
5-
3
8
=4
5
8
,
1
2
-
1
3
=
1
6
,
1
3
-
1
4
=
1
12
,
5
6
+
2
3
=
3
2
,
3
10
+
1
5
=
1
2
,
4
5
-
4
5
=0,
1
4
+
1
3
=
7
12
,
1
2
-
3
8
=
1
8
.
点评:本题考查了简单分数加减法,计算时要细心,注意把结果化成最简分数.