Traveller Walkway

Question

a traveler is walking on a walkway in an airport. the traveler must walk back on the walkway to get a bag he forgot. the traveler’s ground speed is 1ft/s against the walkway and 7ft/s within the walkway. What’s the traveler’s speed off the walkway? What is the speed of the moving walkway?

Answer 1

t+w=7

t-w = 1

add

t+t=7+1

2t=8

t=8/2 =4 mph= traveler's speed

w=7-4=3 mph= walkway speed