1、5508900 5.50.89 55000.89 4895008.9 4895008.9 489508900 三、估算。902198 802302 59303 28338 四、计算。7382.14.3 6950569505 7 7 6 1 1 1.5 84 ( ) 3 5 7 4 3 6 7 1 1 ( ) 73601 7 6 2 6 21045.58 7.393 7 2 6 1 1 9 6 3 5 6 4 4 1 1 1 4 9 46 46 5 8 2 4 13 13 24 1 3 7 3 ( ) 72 19 4 4 6 4 29407079.7 62.527294 四、解方程。 7 x 0
2、.7 4 100x 108 6 x 7 1 10% x x 9 4 3 3 1 1 x : 8 = : 8 : x = 90 : 30 5 6 14 3 = 5 : x = 1.25 : 8 3.6 x 1 0.3 : 0.1 = x : 40 : x = 0.6 : 18 4 1 8 9 1 = = 2 x x 6 1 1 0.4 9 = : 2 = 2 2 0.4 x 1 1 1 : x 7 : x = 3.5 : 2 2 6 4 9016= 98060= 610= 40040= 140.4= 549= 5.40.6= 2025%= 8 6 1 6 1 1 4 = 3 = 7 7 3 7
3、3 3 5 6.910.2= 5.721.31= 0.254= 426= 二、根据64855440,直接写出下面各题的得数。6408.5 0.6485 64000.85 64850 544000850 544000.85 544850 5440.85 498103 798301 8198 42274 25.62.71.6 7430.057430.05 7 4 5 1 1 0.5 120 ( ) 4 5 4 5 6 7 6 1 1 ( ) 66701 8 5 2 10 70.82969 5.510.17 6 2 1 2 1 8 5 3 2 3 4 1 1 1 4 1 1 31 31 4 8 3
4、5 2 2 29 4 1 7 1 48 19 5 5 8 2 5.17471.96 74.644137 x 0.7 9 40x 114 3 x 9 1 45% x x 16 8 4 4 2 = : 0.9 : x = 8 : 100 3 9 4 9 = 0.8 : x = 0.2 : 9 2.8 x 0.8 : 80 = x : 20 : x = 60 : 12 2 3 7 6 4 7 x x 5 1 4 1.4 6 8 = 2 5 1.4 x x 40 : x = 20 : 4 5 9 3 8928= 70030= 1450= 14070= 362.4= 449= 10.5= 5060%= 5 1 1