The speed of the wind and the speed of the dragon in still air are respectively; 142.5 mph and 7.5 mph
<h3>How to calculate the speed?</h3>
The dragon flew 300 miles with the wind in two hours.
After flying against the wind for two hours, he had made 270 miles of the return trip.
Let s be the speed in still air
Let w be the speed of the wind
Thus;
(s - w) = effective speed against the wind
and
(s + w) = effective speed with the wind
We know that;
distance = time * effective speed
Thus;
2(s + w) = 300
2(s - w) = 270
This can be simplified to get;
s + w = 150 -----(1)
s - w = 135 -----(2)
Add both equations to get;
2s = 285
s = 285/2
s = 142.5 mph.
Then, plane speed in still air is;
142.5 + w = 150
w = 150 - 142.5
w = 7.5 mph is the speed of the wind
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