Skip to content / Đến nội dung
ThichHocToan.com

2012 AMC 10B Question 13

AMC10 · 2012 AMC 10B

Question 13

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 $