00:01
Okay, i suppose the wind is moving this way at w miles per hour.
00:08
That's the wind speed.
00:10
Now, let's let the jet speed be x miles per hour in still air.
00:24
No wind plane flies at x miles per hour.
00:29
Now, if we're flying against the wind, i .e.
00:35
This direction in the first case, then the ground speed will be x minus w.
00:42
The plane speed in still air minus the wind speed.
00:47
And then with the wind this way, the speed on ground and the ground will increase to x plus w miles per hour.
00:56
The wind is helping to play along so it's going faster in terms of ground speed.
01:04
Now knowing that, i can then work out hopefully x and w.
01:09
Know that v equals d over t so speed equals distance over time so first case then x minus w so x minus w is the speed distance covered is 4 380 and time taken is 6 hours that's going against the wind so this implies that 4 380 is 6x minus 6 w.
01:50
Then with the wind then the speed is x plus w.
01:59
Distance then is 3 570 and then that's in 3 hours.
02:08
So that implies 3570 is equal to 3x plus 3w.
02:17
Now two equations here and two unknowns.
02:21
I can solve that in 5x and w.
02:24
The best way is times blue 1 by 2 all the way across...