2. A passenger ship with a speed of 13km is sailing in a river, and the water speed of this river is 7km per hour. How many hours does it take for this passenger ship to sail along the river 140km?
The waterway between Port A and Port B is 208km long. A ship sails from port A to port B, arrives at the port in 8 hours, returns to port A from port B, and reaches against the current 13 hours. Seek the speed of the ship in still water?
The distance between the two docks is 360 kilometers. It takes 9 hours for a motorboat to travel a full circle along the river. The flow rate of this river is 5 kilometers per hour. How many hours does it take for this motorboat to travel completely against the current?
5. A boat goes downstream, 5 hours and 60 kilometers, and it takes 10 hour to reach this waterway upstream. What is the ship's speed and current speed?
6. A big river, the flow speed in the middle (main channel) of the river is 8 kilometers per hour, and the flow speed along the coast is 6 kilometers per hour. A boat went downstream in the middle of the river, 13 hours for 520 kilometers. How many hours will it take to send the ship back to its original coastal position?
7. A River is a tributary of B River. The speed of river A is 3 kilometers per hour, and that of river B is 2 kilometers per hour. Ship A sailed along the B River for 6 hours, traveled 84 kilometers to reach the Jia River, and sailed downstream in the Jia River 133 kilometers. How many hours does this ship sail?
8. A cargo fleet sailed 42km downstream and 8km upstream for the first time, which took * * * 1 1 hour; The second time, at the same time, I sailed 24 kilometers downstream and 14 kilometers upstream. What is the speed and current speed of this small fleet in still water?