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2012 AMC 12B Question 9

AMC12 · 2012 AMC 12B

Question 9

It takes Clea $60$ seconds to walk down an escalator when it is not operating, and only $24$ seconds to walk down the escalator when it is operating. How many seconds does it take Clea to ride down the operating escalator when she just stands on it?
  1. $36$
  2. $40$
  3. $42$
  4. $48$
  5. $52$