SOLUTION: A child is running on a moving sidewalk in an airport. When she runs against the sidewalk's motion, she travels in seconds. When she runs with the sidewalk's motion, she travels

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: A child is running on a moving sidewalk in an airport. When she runs against the sidewalk's motion, she travels in seconds. When she runs with the sidewalk's motion, she travels       Log On


   

Question 498778: A child is running on a moving sidewalk in an airport. When she runs against the sidewalk's motion, she travels in seconds. When she runs with the sidewalk's motion, she travels in the same amount of time. What is the rate of the child on a still sidewalk and what is the rate of the moving sidewalk?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let c = rate of child on stationary sidewalk
Let s = rate of moving sidewalk
Let d = length of the sidewalk
Let t = time spent on moving sidewalk
given:
Running against motion of sidewalk
+d+=+%28+c+-+s+%29%2At+
Running with motion of sidewalk
+d+=+%28+c+%2B+s+%29%2At+
The distance and the time are the same in both cases
+c+-+s+=+c+%2B+s+
+-s+=+s+
+2s+=+0+
The sidewalk is not moving