Answer:
Speed of plane in still air is 825 km/h
Explanation:
Given:
Speed of plane with the wind is 145 km/h faster than what it would have with still air.
Speed of plane with wind = 970 km/h
To find speed of plane in still air.
Solution:
Let speed of plane in still air be =

So The speed of plane with wind would be given as =

Now Given:
Speed of plane with wind is given =970 km/h
So, we have:

Now Solving for "x" we get
Subtracting both sides by 145.

Hence, speed of plane in still air is 825 km/h