SOLUTION: It takes a child 90 seconds to climb the 60m length of an escalator which is not working. When in operation, the escalator lifts a passenger from bottom to top in 60 seconds. How

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Question 297628: It takes a child 90 seconds to climb the 60m length of an escalator which is not
working. When in operation, the escalator lifts a passenger from bottom to top in 60 seconds. How long does it take the child to cover the 60 meters, if she walks on the moving escalator?
Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
60/60=1 mps
The escalator lifts at 1 meter per sec.

r*t=d
r=d/t=60/90=2/3 mps
The child goes at 2/3 mps
1+2/3=5/3 mps
together they go 5/3 meters per sec
5/3*x=60
x=60*3/5=12*3=36 seconds