In a river, the ratio of the speed of the current and the speed of a boat in still water is 5 : 6. Again, the ratio of the speed of the current and speed of a steamer is 8 : 9. Find the speed ratio between the speed of boat and steamer.
1
9 : 16.
2
16 : 15
3
14 : 15
4
8 : 9