Question 668883
Since Will want a window seat he steps onto the moving sidewalk and continues to walk while Cheryl uses the stationary sidewalk. if the sidewalk moves at 1 meter per second and Will saves 50 Seconds covering the 300 meter building what is their walking speed
----------
Note: The assumption seems to be that they walk at the same rate.
-------------
Will's DATA:
rate = 1+x meters/sec ; distance 300 meters ; time = 300/(1+x) seconds
------
Cheryl's DATA:
rate = x meters/sec ; distance = 300 meters ; time = 300/x seconds
-----
Equation:
Cheryl time - Will time = 50 seconds
----
300/x - 300/(1+x) = 50
-----
1/x - 1/(1+x) = 1/6
6(1+x) - 6x = x(1+x)
----
x^2+x-6 = 0
(x+3)(x-2) = 0
Positive solution:
x = 2 meters/sec (Their walking speed)
===========================================
Cheers,
Stan H.