(共17张PPT)
整十数加、减整十数
1. 30里面有( )个十
2. 40里面有( )个十
3. 6个十是( )
4. 7个十是( )
3
4
60
70
40座
30座
70
40+30 = (个)
4个十加3个十得7个十,是70。
4+3 =
7
40+30 =
70
40
70 -30 =
你是怎样想的?
1.
50 + 40 =
90 - 40 =
+ =
- =
90
40
50
90
50
90
40
50
3 +2 =
5
30+20 =
50
2.
5 -1 =
4
50-10 =
40
2 +3 +4 =
9
20+30+40 =
90
9 -3 +2 =
8
90-30+20 =
80
3.
-10
60
+30
-70
+60
-40
50
80
10
70
30
3.
-40
80
+20
-50
+30
+6
40
60
10
40
46
数学乐园
欢迎你
帮帮小猴
50 + 50=
60 + 30=
70 – 30=
10 + 70=
80 - 50=
30 + 20=
100
90
40
80
30
50
90-70
70-10
60-20
10+80+6=
80-50+7=
40+20-10=
80-10
20+70
40+50
30+20
90-30
30
猜一猜
小动物后面都藏着什么数?
40 + = 70
50 - = 10
- 20 = 60
40
80
5.
我拔的和你同样多。
一共拔了多少个?
=
20
20
40
+
(个)
4.
60+30 =
90
90-70 =
20
20+40 =
60
60-20 =
40
30+30 =
60
70-10 =
60
80-50 +7 =
37
10+80 +6 =
96
30+70-40 =
60