Question

Flying with the wind, the plane goes 141 km/h. Flying into the wind, the plane only goes 141 km/h. Find the speed of the plane in still air without wind and the speed of the wind.

a) Plane speed in still air = 141 km/h, Wind speed = 0 km/h
b) Plane speed in still air = 70.5 km/h, Wind speed = 70.5 km/h
c) Plane speed in still air = 100.5 km/h, Wind speed = 41.5 km/h
d) Plane speed in still air = 120.5 km/h, Wind speed = 20.5 km/h

Answer 1

The speed of the plane in still air is 141 km/h and the wind speed is 0 km/h.

Step-by-step explanation:

To find the speed of the plane in still air without wind and the speed of the wind, we can set up two equations. Let's assume the speed of the plane in still air is 'p' km/h and the speed of the wind is 'w' km/h.

So, when the plane is flying with the wind, its total speed is the sum of the plane's speed in still air and the wind speed: p + w = 141 km/h.

Similarly, when the plane is flying into the wind, its total speed is the difference between the plane's speed in still air and the wind speed: p - w = 141 km/h.

From these two equations, we can solve for p and w. Adding the two equations together, we get: 2p = 282 km/h. Therefore, p = 141 km/h. Substituting p back into one of the equations, we get: 141 - w = 141. Solving for w, we find that w = 0 km/h.

Therefore, the speed of the plane in still air is 141 km/h and the wind speed is 0 km/h.