Problema Solution

the speed of a moving sidewalk at an airport is 3ft/sec. A person can walk 87 ft forward on the moving sidewalk in the same time it takes to walk 12 ft on a nonmoving sidewalk in the opposite direction. At what rate would a person walk on a nonmoving sidewalk?

Answer provided by our tutors

Let

v = 3 ft/sec the speed of the moving sidewalk

v1 = the rate of the person

t = the time of the walk in each direction

Walking forward on the moving sidewalk the rate of the movement is: v + v1 = 3 + v1

Walking on non moving sidewalk in opposite direction the rate of the movement is: v1

Since distance = speed*time we have:

(v + v1)*t = 87

(3 + v1)*t = 87

Walking on non moving sidewalk in opposite direction the rate of the movement is v1:

v1*t = 12 divide both sides by v1

t = 12/v1

Plug t=12/v1 into (3 + v1)*t = 87 we get:

(3 + v1)*(12/v1) = 87

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click here to see the equation solved for v1

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v1 = 0.48 ft/s

The rate of the person on a non-moving sidewalk is 48 feet per second.