0+7= 4-2= 5-0= 1+6=
9-3= 0+9= 8+1= 4+4=
7-5= 5-3= 6+2= 1+7=
7-3= 9-4= 2+7= 5-4=
|
1 |
|
3 |
|
5 |
|
7 |
|
9 |
|
8 |
|
6 |
|
4 |
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2 |
1 |
|
5-1=□
4-□=□
□-□=□
3-□=□
一共有( )只,右边有( )只。左边有几只?
+2=5, =。