Question

Flying to England with a tailwind a plane averaged 158km/h one the return trip the plane only averaged 112 km/h while flying back in the same wind. Fund the speed of the wind and the plane still in the air.

Answer 1

Answer: the speed of the plane in still air is 135 km/h

the speed of the wind is 23 km/h

Explanation:

Let x represent the speed of the plane in still air.

Let y represent the speed of the wind.

Flying to England with a tailwind a plane averaged 158km/h. This means that the total speed of the plane is (x + y) km/h. Therefore,

x + y = 158 - - - - - - - - - - - - - -1

On the return trip, the plane only averaged 112 km/h while flying back in the same wind. This means that the total speed of the plane is (x - y) km/h. Therefore,

x - y = 112 - - - - - - - - - - - - - -2

Adding equation 1 to equation 2, it becomes

2x = 270

x = 270/2 = 135 km/h

Substituting x = 135 into equation 2, it becomes

135 - y = 112

y = 135 - 112

y = 23 km/h