信息窗1练习设计
1、填空
(1)4 6 20 10
(2)3 4 2 6
(3)4 6
(4)2 :4 = 5 :10
(5)10
(6)45
2、(1)5 : 2
(2)5 :2
(3)能 50 :20 = 100 :40
3、4 :2 = 0.8 :0.04
36 :24 = 60 :40
20 :40 = 0.8 :1.6
20 :10 = 12 :6
4、2 :3 = 4 :6
1/3 :¾ = 4 :9
5、(1)20 :5 = 4 :1 = 4
24 :8 = 3 :1 = 3
40 :10 = 4 :1 = 4
45 :15 = 3 :1 = 3
28 :14 = 2 :1 = 2
40 :20 = 2 :1 = 2
120 :25 = 24 :5 = 24/5
(2)28 :14 = 40 :20
6、35 2/5 14
2 7 14
35 :2 = 7 :2/5
2 3/4 3/2
16 1/8 2
7、80 ÷ 5 = 16
16 × 4 = 64(枚)
8、6x = 8 × 18
x = 24
6.9x = 23 × 3
x = 10
16x = 5 × 40
x = 12.5
1/8x = 1/4 × 1/5
x = 2/5
1.5x = 4.5 × 3
x = 9
2.1x = 3 × 0.7
x = 1
9、(1)5 :8 = 40 :x
5x = 40 × 8
x = 64
(2)x :3/4 = 1/5 :2/5
x = 3/8
10、(1)3 + 5 = 8
男:320 × 3/8 = 120(人)
女:320 × 5/8 = 200(人)
(2)120 + 10 = 130(人)
200 + 10 = 210(人)
130 :210 = 13 :21