It takes a plane 40 minutes longer to fly from Boston to Los Angeles at 525 miles per hour than it does to return at 600 miles per hour. How far apart are the cities?

Question

It takes a plane 40 minutes longer to fly from Boston to Los Angeles at 525 miles per hour than it does to return at 600 miles per hour.  How far apart are the cities?

drwls · Accepted Answer

Let T be the shorter of the two times (in hours), and D be the distance 600 T = D 525 (T + 2/3) = D = 525 T + 350 600 T = 525 T + 350 75 T = 350 T = 4 2/3 hours D = 600 T = 2800 miles