Flying to the wind, an airplane takes 4 hours to go 960 km. The same plane flying with the wind takes only 3 hours to make the same trip. Find the speed of the plane and the speed of the wind.

Question

I wasn't here for the lesson from my teacher but told me to ask my classmates but there not replying to me. I know distance = speed over time. I tryed using the substituion method but idk i just mess up. Thanks.

Answer 1

You have to consider the speed of the plane without wind and the speed of the wind itself

Let the speed of the plane in still air be x km/h
le the speed of the wind be y km/h

so going with the wind -- speed is x+y mph
going against the wind -- speed is x - y mph

2 equations:
4(x-y) = 960
4x - 4y = 960
x - y = 240 ----- #1

3(x+y) = 960
3x + 3y = 960
x + y = 320 ----#2

these are easy to solve, just add them and after that its simple