7777×9+111×37
=7777(10-1)+111(30+7)
=77770-7777+3330+777
=77770+3330-7000
=70770+3330
=71100
简算7777×9+111×377777×9+111×37（要简算哦)
7777×9+111×37
=7777(10-1)+111(30+7)
=77770-7777+3330+777
=77770+3330-7000
=70770+3330
=71100