412•2=824
824-624=200;
231•3=693
857-693=164;
242•2=484
484-156=328;
111•7=777
123+777=900;
221•4=884
884+56=940;
203•3=609
98+609=707;
121•3=363
576-363=213;
221•2=442
900-442=476;
111•5=555
1000-555=455
10 9 10
···
800
-
527
-------
273
9 целых 3/7+2/7=9 целых 5/7