Answer:
Explanation:
Let x represent the speed of the plane.
Let y represent the speed of the wind.
Flying Against the Wind an airplane travels 2640 km in 4 hours. This means that the total speed while flying against the wind will be x - y. Speed = distance/time. Therefore
x - y = 2640/4 = 660 - - - - - - -1
Assuming that in still air, the airplane moves in the same direction with the wind. Total speed in still air will be
x + y
Flying with the wind, the same plane travel 7700 km in 7 hours.
Speed = distance/time. Therefore
x + y = 7700/7 = 1100 - - - - - - - 2
Add equation 1 and equation 2. It becomes
2x = 660 + 1100 = 1760
x = 1760/2 = 880
y = 1100 - x
y = 1100 - 880 = 220
The speed of the plane in still air is 880 km/hour
The speed of the wind is 220 km/ hour
Rate of the plane in still air is 1100 km/hour
Rate of the plane against the wind is 880- 220 = 660 km/h