AGAINST THE WIND

Question

Against the wind a commercial airline in South America flew
728 miles in 4 hours. With a tailwind the return trip took
3.5 hours. What was the speed of the plane in still? air? What was the speed of the? wind?

Answer 1

distance=rate*time

d=rt

728=(r-w)*4

728=(r+w)*3.5

divide both sides of first equation by 4 and divide both sides of second equation by 3.5

182=r-w

208=r+w

add

390=2r

r=195 mph for the speed of the plane

182=195-w

195-182=w

w=13 mph for the speed of the wind