1. The problem statement, all variables and given/known data Pilots are racing small, relatively high-powered airplanes arounds courses marked by a pylon on the ground at each end of the course. Suppose two such evenly matched racers fly at airspeeds of 130 mi/h. Each flies one complete round tripof 25 miles, but their courses are perpendicular to one another and there is a 20mi/h windblowing steadily parallel to one course. (a). Which pilot wins the race and by how much? 2. Relevant equations I think this is a Galilean transform'ation problem. I label the two planes A and B. for plane A , I'll say its velocity u'(A) = u(A)-v , where v is the velocity of the windblowing at 20mi/h and for plane B (u)'(B)=(u)(B). It doesn't really matter but I'll just say the velocity of the wind is parrallel to plane A , but it doesn't really matter. 3. The attempt at a solution For plane A, u'(A)=u(A)-v -> u'(A)= 130mi/h -20mi/h = 110mi/hr For plane B , u'(B)=u(B) = 130 mi/hr In order to determin which plane wins the race by howmuch I am going to have to determine how much time it will take the planes to arrive at d=25 miles, where d is the total completion of the course for time A , t(A) = d/u'(A) = (25mi/110mi/hr)*3600 s = 818.18 seconds for time B , t(B) = d/u'(B) = (25 mi/130mi/hr) * 3600 s = 692.307 seconds so plane A should arrive at the finish before plane B and plane A wins by delta(t)=t(A)-t(B)= 818.18 secs-692.307 secs =125.87 seconds but my answer isn't even remotely close to the answer in my textbook. I redid my calculations over and over again and still arrive to the same time intervals. What am I doing wrong?