



 
Hi Selby, There are two keys to solving this problem. One is your final statement "Distance = speed x time". The second is that if you are flying with the wind then your speed increases by the speed of the wind and if you are flying against the wind then your speed decreases by the speed of the wind. Thus for example if your speed in still air is 100 km/hr then your speed with the wind is 100 + 40 = 140 km/hr and your speed against the wind is 100  40 = 60 km/hr. But you don't know the speed in still air so suppose it's s km/hr.
These two distances are the same. Solve for s. Penny  


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