题目内容
先通分,再比较每组分数的大小.
和
和
和
和
.
| 2 |
| 5 |
| 3 |
| 10 |
| 5 |
| 6 |
| 4 |
| 7 |
| 3 |
| 8 |
| 5 |
| 12 |
| 11 |
| 24 |
| 2 |
| 3 |
分析:找出每组分数的分母的最小公倍数,再根据分数的基本性质,把它们变成分母是它们最小公倍数的而分数值大小不变的分数,然后再比较大小.
解答:解:(1)
=
=
,
>
,所以
>
.
(2)
=
=
,
=
=
,
>
,所以
>
.
(2)
=
=
,
=
=
,
<
,所以
<
.
(4)
=
=
,
<
,所以
<
.
| 2 |
| 5 |
| 2×2 |
| 5×2 |
| 4 |
| 10 |
| 4 |
| 10 |
| 3 |
| 10 |
| 2 |
| 5 |
| 3 |
| 10 |
(2)
| 5 |
| 6 |
| 5×7 |
| 6×7 |
| 35 |
| 42 |
| 4 |
| 7 |
| 4×6 |
| 7×6 |
| 24 |
| 42 |
| 35 |
| 42 |
| 24 |
| 42 |
| 5 |
| 6 |
| 4 |
| 7 |
(2)
| 3 |
| 8 |
| 3×3 |
| 8×3 |
| 9 |
| 24 |
| 5 |
| 12 |
| 5×2 |
| 12×2 |
| 10 |
| 24 |
| 9 |
| 24 |
| 10 |
| 24 |
| 3 |
| 8 |
| 5 |
| 12 |
(4)
| 2 |
| 3 |
| 2×8 |
| 3×8 |
| 16 |
| 24 |
| 11 |
| 24 |
| 16 |
| 24 |
| 11 |
| 24 |
| 2 |
| 3 |
点评:本题主要考查了学生对通分知识的掌握情况,以及根据通分的知识比较异分母分数大小.
练习册系列答案
相关题目