SOLUTION: 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 a

Algebra ->  Equations -> SOLUTION: 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 a      Log On


   

Question 1024862: 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.
Found 2 solutions by josgarithmetic, MathTherapy:
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
RT=D basic rule; set up a data table. 

                           rate           time             distance

home to airport            30             x%2F30                  x

airport to offices         90             y%2F90                  y

totals                                    2                 140

You want to solve for the value of y.

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!
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%2F90+%2B+%28140+-+D%29%2F30+=+2

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 = %28-+240%29%2F%28-+2%29, or highlight_green%28120%29 miles