A man can walk up a moving "up" escalator in 30s. The same man can walk down this moving "up" escalator in 90s. Assume that his walking speed is same upwards and downwards. How much time will he take to walk up the escalator, when it is not moving?
(a) 30s
(b) 45s
(c) 60s
(d) 90s

• Let the speed of the man and escalator are x and y.
  So 30(x+y)=90(x-y)
  y=1/2*x
  Agn when escalator is off.let the tym taken by man is t sec.
  Distance is same so that
  t*x=90(x-y)
  After solving t=45..
  Ans.. 45 sec..
• 10 years agoHelpfull: Yes(4) No(0)