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用简便方法计算:286+879-679812-503+193368+1859-859582+393-293

题目详情
用简便方法计算:286+879-679 812-503+193 368+1859-859 582+393-293
▼优质解答
答案和解析
286+879-679
=286+200+679-679
=486
812-503+193
=812-503+193+10-10
=812-503+203-10
=812-300-10
=512-10
=502
368+1859-859
=368+1000+859-859
=1368
582+393-293
=582+100+293-293
=682