Matt and anna often fly between two cities that are a distance of 1680 miles apart. on one particular trip, they flew into the wind and the trip took 4 hours. the return trip with the wing behind them, only took about 3 hours. find the speed of the wind and the speed of the plane in still air.

Speed = Distance / Time

So, when the wind is against the plane:

Speed = 1680/4 = 420 mph

When the wind is with the plane:

Speed = 1680/3 = 560 mph

So:

Plane + Wind = 560
Plane - Wind = 420

P + W = 560
-(P - W = 420)

2W = 140
W = 70

If W = 70, P = 560 - W = 560 - 70 = 490

So the wind speed is 70 mph, and the plane speed in still air is 490 mph

HERE IS YOUR ANSWER IN PICTURE..