The ship

The ship went upstream speed of 20 km/h in relation to water. River flows at speed 10 km/h. After half an hour, he stopped and returned downstream to the starting point. How long it took way back when even if downstream speed of ship is 20 km/h in relation to water?

Result

t =  10 min

Solution:


(20-10)*30 = (20+10)*t

30t = 300

t = 10

Calculated by our simple equation calculator.







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