46-836 5448+8
10个十1个百 80+990+8
56+20= 63-9= 49-20= 44+7= 100-60=
35+30= 90-8= 8+72= 6+38= 22-6=
41-9+50= 80-(18-9)= 37+5-20=
21-(7+2)= 84-50+7= 52-(10-3)=
-9=38 65-=60 +20=44
+30=100 17-=9