Question

A helicopter leaves Rogers airport and flies north at 180 mph. One hour later a plane leaves the airport and follows the helicopter at 330 mph. How long does it take the plane to catch up to the helicopter?

Answer 1

distance = speed * time

The plane catches the helicopter when they both traveled the same distance, d.
The helicopter traveled t hours, but the plane traveled 1 hour less, or t - 1 hours.

helicopter:
d = 180t

plane:
d = 330(t - 1)

The distance they both traveled, d, is the same, so

180t = 330(t - 1)

180t = 330t - 330

-150t = -330

t = (-330)/(-150)

t = 2.2

The helicopter traveled 2.2 hours, so the plane traveled 1.2 hours.

Answer: The plane catches the helicopter after 1.2 hours of plane flight.