posted by joe .
it takes a plane 40 min longer to fly from boston to los angeles at 525 mi/h than it does to return at 600 mi/h. how far apart are the cities?
distance = rate*time
B to LA = 525mi/hr*t
La to B = 600mi/hr*t
The distance is the same no matter which way we go, but we must ADD 40 minutes to the time for B to LA because the plane is flying slower. So 40 minutes is 40/60 hours and we add that to t. Therefore, B to LA = 525*(t+.6667)
Now set distance = distance.
Solve for t which gives the time to fly from LA to B. Then time x 600 mi/hr = distance traveled. Post your work if you get stuck.
actually i don't think that is right sorry.