1、15001400 0.1514 151400 150001.4 21000.14 21001400 210000.14 2.1三、估算。499299 599196 87397 30361 四、计算。42803.21.8 40.64040.640 5 9 4 1 1 1.5 120 ( ) 4 5 3 8 5 2 7 1 1 ( ) 34598 3 6 2 10 587.80.62 7010.77 6 1 1 1 6 3 7 3 7 3 7 1 1 1 1 2 1 43 43 2 7 3 4 3 3 5 5 1 7 1 ( ) 24 3 6 6 6 2 12252516.5 46.943296
2、四、解方程。 7 x 0.3 3 0.4x 54 4 x 13 6 20% x x 49 7 7 7 1 1 x : 6 = : 20 : x = 60 : 5 5 7 4 3 = 0.8 : x = 0.2 : 9 4.4 x 7 50 : 3 = x : 0.5 : x = 6 : 18 8 1 5 8 3 = = 2 x x 2 9 1 2 3 = : 8 = 8 2 0.4 x 1 1 1 : x 70 : x = 35 : 8 4 6 7 9710= 750570= 730= 33030= 143= 724= 3.50.7= 2290%= 3 1 1 1 2 3 3 = 4 = =
3、2 2 2 3 3 4 2 6.641.82= 5.40.86= 0.252= 366= 二、根据16651040,直接写出下面各题的得数。1.66.5 0.166500 1.66500 0.0160.65 1046500 1040006.5 10400.65 1046.5 503302 897302 63402 35744 36401.75.2 2.570.042.570.04 13 3 4 1 1 7.5 48 6 5 3 4 4 6 8 1 1 ( ) 6598 7 7 4 6 190.13090 83.37.4 5 2 1 1 1 5 6 3 4 2 8 1 1 1 1 4 1 32
4、32 3 8 2 2 5 5 26 1 7 7 1 ( ) 48 17 8 8 8 2 828466380 97.82064 x 0.1 4 200x 78 3 x 5 1 65% x x 4 2 2 2 7 = : 9 : x = 90 : 2 2 9 4 2 = 20 : x = 5 :1.2 x 9 3 : 0.6 = x : 90 : x = 9 : 150 1 5 7 1 2 x x 6 1 4 0.6 2 4 = 2 5 1.4 x x 60 : x = 30 :3 6 8 803= 730530= 1840= 18060= 252.7= 514= 3.60.6= 620%= 3 1