All helicopter leaves central airport and flies North at 180 mph. 20 minutes later a plane leaves the airpor

helicopter-leaves

#1

All helicopter leaves central airport and flies North at 180 mph. 20 minutes later a plane leaves the airport and follows the helicopter at 330 mph. How long does it take the plane to overtake the helicopter?

Answer:

Let the time taken by plane to overtake the helicopter be t.

distance = speed * time

When the plane overtakes the helicopter, the two distances are equal.

180 * (t + 20/60) = 330 * t
180 t + 60 = 330 t
150 t = 60
t = 60/150 = 0.4 hr = 24 minutes.