Problema Solution
Flying to Kampala with a tailwind a plane averaged 158 km/h. On the return trip the plane only averaged 112 km/h while flying back into the same wind. Find the speed of the wind and the speed of the plane in still air.
Answer provided by our tutors
The averages are given. So that means the first trip is the equivalent of of 158 miles in one hour. Since this is with the wind, using the distance = rate x time, we have :
158 = (a + w) 1, where a = airspeed, w - wind speed, and 1 is the time.
For the second one, 112 = (a - w) x 1, a = airspeed, etc.
158 = a + w
112 = a - w Add the two equations
270 = 2a
135 = a So the airspeed is 135 km/h
158 = 135 + w
23 = w The windspeed is 23 km/h