4+5= 8+1= 2+7=
4+6= 8+2= 3+7=
4+7= 8+3= 4+7=
观察每一组题,你准备先做哪一题?为什么这样做?
4+7=
6+6=
7+6=
7+8= 9+8= 6+7-3= 9-6=
10+7= 9-5+5= 6+8= 0+6=
18-8= 7+3-8= 9+9= 17-0=
19-4-3= 4+8+2= 16-3= 3+8=
5+( )=11 ( )-3=5 10-( )=7 7+4=( ) +2
10+1= 10+4= 10+9= 10+7=
10+2= 10+8= 10+6= 10+3=
14-4= 17-7= 16-6= 19-9=
12-2= 15-5= 11-1= 13-3=