An executive drove from home at an average speed of 30 mph to an airport where a helicopter was waiting. The executive boarded the helicopter and flew to the corporate offices at an average speed of 90 mph. The entire distance was 140 mi. The entire trip took 2 h. Find the distance from the airport to the corporate offices.
Let distance from airport to the office, be D
Then distance from home to airport = 140 D
We then get the following TIME equation:
D + 3(140 D) = 2(90) ------ Multiplying by LCD, 90
D + 420 3D = 180
D 3D = 180 420
2D = - 240
D, or distance from the airport to the office = , or miles