1、单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,尝试与猜测,鸡兔同笼,有,9,个头,,26,条腿。鸡、兔各有几只?,鸡有几只,兔有几只,腿有多少条,1,8,34,2,7,32,3,6,30,4,5,28,5,4,26,鸡有几只,兔有几只,腿有多少条,1,34,138,2,33,136,3,32,134,4,31,132,23,12,94,鸡有几只,兔有几只,腿有多少条,17,18,106,20,15,100,22,13,96,23,12,94,乐乐的储蓄罐里有,1,角和,5,角的硬币共,27,枚,总值,5.1,元,,1,角和,5,角的硬币各有多少枚?,1
2、角,/,枚,5,角,/,枚,总值,/,元,13,14,8.3,18,9,6.3,20,7,5.5,21,6,5.1,1,角硬币,21,枚,,5,角硬币,6,枚。,鸡兔同笼,有,20,个头,,54,条腿,鸡兔各多少只?,假设法,假设笼中全是鸡,腿有,20,2=40,(条),;,与实际相比,少了,54,40=14,(条),一只兔当成一只鸡来算,比实际少,4,2=2,(条),14,中有多少个,2,,就有多少只兔子,14,2=7,(只),兔:(,54,2,20,),(,4,2,),=7,(只),鸡:,20,7=13,(只),解:设有,x,只兔,那么就有(,20,x,)只鸡。,鸡兔共有,54,条腿,,就是:,4,x,2,(,20,x,),=54,2,x,40 =54,2,x,=14,x,=7,20,7=13,(只),答:免有,7,只,鸡有,13,只。,列方程法,鸡兔同笼,有,20,个头,,54,条腿,鸡兔各多少只?,鸡兔同笼,有,17,个头,,42,只脚。鸡、兔各有多少只?,用大小卡车往城市运,29,吨蔬菜,大卡车每辆每次运,5,吨,小卡车每辆每次运,3,吨,大小卡车各用几辆能一次运完?,