□○□=□(个)
14-7= 8+40= 66+4= 11-3=
24+5= 54-30= 78-70= 57-9=
6+28= 20+57= 62-7= 48+8=
17-9= 70-8= 5+28= 12-5=
85-5= 16+50= 13-7= 90+3=
40+30= 90-40= 30+24= 80-4=
12-3= 13-7+5= 3+9+2= 15-8+3=
12-5= 8+3-5= 12-3-4= 17-5+4=
12-4= 14-7+8= 6+7-4= 16-3-8=
13-7= 13-6= 13-5= 13-5+6=
44-8= 68+7= 56-7= 56+8= 61-40-8=
3.8+0.62= 0.15×0.8= 0.1:0.01= 0.5吨:50千克=
10×10%= ÷12= 1.6+0.4×10= =