Edward A. answered 12/20/19
Math Tutor, Retired Computer Scientist and Technical Communicator
We assume that the effective speed into a headwind is (planespeed - headwind) and effective speed with a tailwind is (plane speed + tailwind).
So, assuming the headwind in one direction is the same magnitude as the tailwind in the other,
planespeed + wind = 158 km/h
planespeed - wind = 112 km/h
Two equations in two unknowns:
add the two to get 2*planespeed = 270
planespeed = 135
Then, Becky, substitute into either equation and solve for wind speed.