1、82009.9 829.9 820099000 811.899 81189900 81.180.99 81.1899 三、估算。502102 902398 78304 23841 四、计算。29005.34.9 96900.0296900.02 3 1 5 1 1 9.5 144 ( ) 2 5 6 3 8 7 6 1 1 ( ) 18498 6 5 6 10 62530.45 62.10.96 6 1 6 1 1 7 5 2 5 5 7 3 1 1 1 1 4 31 31 4 10 3 5 5 5 19 4 1 5 1 ( ) 48 11 5 5 6 4 576968.86 87.42223
2、4 四、解方程。 7 x 0.8 9 4x 116 6 x 3 5 65% x x 12 8 2 6 1 1 x : 6 = : 0.7 : x = 0.5 : 0.8 3 7 12 7 = 6 : x = 1.5 : 3 4 x 1 3 : 60 = x : 70 : x = 90 : 18 7 2 9 6 7 = = 3 x x 8 1 1 0.4 3 = : 7 = 3 3 1.6 x 1 1 1 : x 7 : x = 3.5 : 2 5 8 6 9253= 870480= 1330= 15030= 92.6= 949= 0.40.2= 840%= 9 1 4 3 7 7 1 = 7
3、= 5 5 7 4 6 8 4 5.871.24= 5.31.5= 0.1254= 2.73= 二、根据67785226,直接写出下面各题的得数。67000.78 677800 0.67780 0.067780 5226780 522678 522607.8 522600899297 602199 72304 17994 84601.83.5 2000420004 11 2 4 1 1 7.5 84 ( ) 5 5 3 4 7 2 5 1 1 ( ) 53599 3 4 2 6 57.4381.2 2076.4 8 1 1 1 1 2 7 2 6 4 6 1 5 1 1 1 4 3 3 2 6
4、 4 2 5 5 10 1 4 6 3 ( ) 20 7 5 5 5 4 1710905990 66.43152 11 x 0.5 3 0.8x 54 5 x 11 1 80% x x 15 2 5 3 8 = : 0.6 : x = 40 : 4 2 6 6 5 = 40 : x = 10 :0.8 x 4 20 : 0.5 = x : 20 : x = 30 : 5 1 2 7 5 5 x x 4 1 1 1.6 9 2 = 4 5 1 x x 6 : x = 3 : 9 5 7 7 9737= 850420= 1330= 3010= 572.2= 612= 20.5= 450%= 5 1 1