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解法一
218×730+7820×73
=(218×10)×(730÷10)+ 7820×73
=2180×73+7820×73
=(2180+7820)×73
=10000×73
=730000
解法二
=218×730+(7820÷10)× (73×10)
=218×730+782×730
=(218+782)×730
=1000×730