1. The problem statement, all variables and given/known data a plane flies at an airspeed of 250 km/h. A wind is blowing at 80 km/h toward the direction 60(degrees) east of north. a) in what direction should it fly in order to fly north relative to the ground? b) what is the speed of the plane relative to the ground? 2. Relevant equations Pythagorean theorem? tan-1(y/x)=theta 3. The attempt at a solution http://img709.imageshack.us/img709/8219/15610642.png [Broken] the back of the book states: a) 16 west of north b) 280 km/s (i think it means km/h) i get a) 108 (18 west of north) b) 221 km/h wtf? now that i look over it, i'm not really sure where the 250 goes. If the plane travels at 250 km/h and the wind also it pushes north-east, then it should be going faster.