27+197x9+13x297的简便计算
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你好,27+197x9+13x297=27+(200-3)x9+13x(300-3)=27+200x9-3x9+13x300-13x3
咨询记录 · 回答于2022-09-01
27+197x9+13x297的简便计算
你好,27+197x9+13x297=27+(200-3)x9+13x(300-3)=27+200x9-3x9+13x300-13x3
=27+1800-27+3900-39=1800+3900-39=5700-39=5661
结果等于5661
2018x2020一2017x2021的简便计算
197=200-3,297=300-3,有零更方便计算
2018x2020一2017x2021=2018x2020-2017x(2020+1)=2018x2020-2017x2020-2017=(2018-2017)x2020-2017=2020-2017=3
2018x2020一2017x2021=3
2018x2020-2017x2020=(2018-2017)x2020=2020