A plane can fly 360 miles in the same time as it takes a car to go 120 miles. If the car travels 120 mph slower than the plane, find the speed of the plane.

Question

I hate word problems and cannot seem to solve them. Help please :(

Answer 1

speed = distance/time

time = distance/speed

 

let the speed of the plane be x mph

so time = 360/x

 

speed of the car = x - 120

so time = 120/x-120

 

Since the two times are equal:

 

360/x = 120/(x-120)

 

or, x/360 = (x-120)/120

 

      x/3   = x -120

      x = 3x - 360

      2x = 360

        x = 180 mph