人教版数学五年级上册第三单元练习八课件

,第,3,单元,练习八,1,求出下面各题中商的近似值。,（,1,）保留一位小数。,48,2.3,1.55,3.8,7.09,0.52,20.9,0.4,13.6,（,2,）保留两位小数。,3.81,7,246.4,13,5.63,6.1,0.54,18.95,0.92,2.,一支铺路队正在铺一段公路。上午工作,3.5,小时，铺了,164.9 m,；下午工作,4.5,小时，铺了,206.7 m,。是上午铺路的速度快，还是下午铺路的速度快？,164.9,3.547.1(,米,/,时,)206.7,4.545.9(,米,/,时,),45.9,47.1,答：所以上午铺路的速度快。,2.9,2.86,2.857,0.9,0.85,0.851,1.2,1.20,1.197,3.,4,蜘蛛的爬行速度大约是蜗牛的几倍？你能提出数学问题并解答吗？,动物名称,爬行的速度,蜗牛,0.045,千米,/,时,陆龟,0.32,千米,/,时,蜘蛛,1.9,千米,/,时,1.9,0.04542,答：蜘蛛的爬行速度大约是蜗牛的,42,倍。,例：陆龟的爬行速度大约是蜗牛的几倍？,0.32,0.0457,(,所提问题不唯一,),0.5,40.5 81 1.5,54,81 0.5,162 81 1.5,82.5,5.,在 里填上合适的运算符号。,6,列竖式计算。,5.7,9,6.64,3.3,5,8,9.4,6,0.63,2.012,0.625,1.56,5.7,9,，,6.64,3.3,，,9.4,6,的商是循环小数。,7,写出下面循环小数的近似值（保留三位小数）。,1.29090,_,0.0183,_,0.444,_,7.275,_,1.291,0.018,0.444,7.275,8,一列火车从南京到上海运行,305 km,，用了,2.6,小时。平均每小时行多少千米？,305,2.6,117.31,（,km,）,答：平均每小时行,117.31 km,。,9.,你会比较这些小数的大小吗？试试看！,0.33,1.233,10,王叔叔一共要买,30,盒牛奶。请你算一算，哪家超市便宜？一共需要多少钱？,从,A,超市买：,58,(30,24),2.5,73(,元,),从,B,超市买：,62,(30,24,2),2.6,72.4(,元,),73,元,72.4,元,答：从,B,超市买便宜，一共需要,72.4,元钱。,11,计算下面各题。,42,28=7.2,1.6+0.8=19.8,3.3=,2.5,3.6=,（,16.8+1.47,）,0.7=18,0.45=,1.5,5.3,6,9,26.1,8.1,12,用计算器计算前三题，找出规律，直接写出后三题的得数。,1234.5679,9,_,1234.5679,18,_,11111.1111,22222.2222,1234.5679,27,_,1234.5679,36,_,1234.5679,45,_,1234.5679,54,_,33333.3333,44444.4444,55555.5555,66666.6666,13,不计算，运用规律直接填出得数，再用计算器验算。,444.222,4444.2222,1,7,2,7,3,7,4,7,5,7,6,7,0.142857142857,0.571428571428,0.714285714285,0.857142857142,0.285714285714,0.428571428571,14.,用计算器计算下面各题。,15,先找出规律，再按规律填数。,（,1,）,6.25 2.5 1 _ _ 0.064,（,2,）,7 3.5 1.75 _ _ 0.21875,0.4,0.16,0.875,0.4375,