(共18张PPT)
乘法分配律在分数中的应用
乐乐
天天
25×36+64×25
左面的题怎样算简便?应用了哪些运算定律?
=(36+64)×25
=100×25
=2500
两列火车同时从两站相对开出,甲车每时行105千米,乙车每小时行95千米,经过
小时相遇。两站间的铁路长多少千米?
甲车
乙车
探究学习
闯关挑战赛
基础关
1
2
3
4
5
强化关
1
2
3
4
拓展关
1
2
1.
×5+
×3
=(5+3)×
=8×
=1
2.
×
=(
+
)×
=1×
=
+
×
3.
×
=
=1×
=
+
×
=(
+
)×
×
+
÷
4.
×
=
=2×
=
+
×
=(
+
+1)×
×
+
×
+
+
×1
5.
=
=
×
=
2-
12
5
4
3
6
5
(
-
)÷
5
12
4
3
6
5
(
-
)
×
-
×
=
(
)
1.
+
-
×
36
=
×
×
×
36
36
36
+
-
=
16
=
12+6-2
(
)
2.
+
-
×
12
=
×
×
×
12
12
12
+
-
=
9
=
8+3-2
3.
101×
=(
100+1)×
=100×
+1×
=44+
=44
4.
97×
=(
98-1)×
=98×
-1×
=97-
=96
1.
26×28×(
+
)
=
26×28×
+
26×28×
=
+
=2
2.
=
=
(
+
)
=
1
=
×
+
×
×
+
×
×
×
通过这节课的学习,你们收获了什么?
课堂小结