笔算减法(不连续退位),验算,6,借出93本,还剩多少本?,21593(),6,21593(),你能用竖式计算吗?先算一算,再和同学交流。,215,93,2,2,百十个,1,6,减法可以怎样验算?,验算一下,看看结果是否正确。,+93,5,1,2,2,2,1,21593(),122,本,215,93,2,2,1,答:还剩本。,122,用竖式计算643580、764429,并验算。,643,580,63,63,+580,643,验算:,764,429,335,335,+429,764,验算:,1.,745,438,7,0,3,926,846,0,8,239,54,5,8,1,2.,355142,62854,936863,142213,54574,86373,628,54,4,7,5,936,863,3,7,355,142,3,1,2,54,574,8,2,6,863,73,6,3,9,142,+213,5,5,3,3.用竖式计算,并验算。,547413,67049,305121,847755,