简便计算.3.14×31.4+628×0.686+68.6×6.86今晚就要!

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简便计算.3.14×31.4+628×0.686+68.6×6.86今晚就要!
简便计算.3.14×31.4+628×0.686+68.6×6.86
今晚就要!

简便计算.3.14×31.4+628×0.686+68.6×6.86今晚就要!
=3.14*100*31.4/100+628*0.686+68.6*10*6.86/10
=314*0.314+628*0.686+686*0.686
=314*0.314+(628+686)*0.686
=314*0.314+1314*0.686
=314*0.314+(314+1000)*0.686
=314*0.314+314*0.686+686
=314+686
=1000

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