Man Walking on Moving Escalator

 A man can walk up a moving "up" escalator in 30 seconds. He can walk down this moving "up" escalator in 1-1/2 minutes. If his walking pace is the same going upstairs as downstairs, how long would it take him to climb the escalator if it was stationary? How long would it take him to go up the moving escalator if he stood still?

Calculated here!