SOLUTION: A traveler is walking on a moving walkway in an airport. The traveler must walk back on the walkway to get a bag he forgot. The travelers ground speed is 2ft/s against the walk way

u + v = 6   ft/s    (the traveler' speed with the walk way)
u - v = 2   ft/s    (the traveler' speed against the walk way)

----------------------------Add the equations.


Answer.  The traveler' speed off the walkway  u= 4 ft/s;  the speed of the moving walkway  v= 2 ft/s.