write yes if the two rations form a proportion no if not

A,
1,4:5 = 16:20
2,5:4 = 10:4
3,6:5 = 30:25
4,3:6 = 6:12
5,11:9 = 30:24

B,pair up two rations that form proportion .
6,12:15
7,2:6
8,5:12
9,39/2
10,16/4