8 :11= 16 :____
7:6=____:30
9:___= 36 :28
2:____= 4:18
____:4= 21:28
_____:4 = 40 :32
6:105 = 2:_____
240:280 =____:7
____:48 = 11:2
3:8=36 :____
_____:190=7:10
252:112=9 :______