0.5:0.35 = 10 :7
1.2:1 = 6 ; 5
5/6:1/9 = 15 :2
2:1/4 = 8 :1
30克：2千克 = 3 :200
3升：450毫升 = 20 :3拖式0.5:0.35 = 50:35 = 10 : 7

1.2:1 = 12:10 = 6 ; 5

5/6:1/9 = 15 :2

2:1/4= 8 : 1

30克：2千克 = 30 : 2000 = 3 : 200

3升：450毫升 = 3000 :450 = 20 : 3