Question

A man can walk up a moving 'up' escalator in 30 s. The same man can walk down this moving 'up' escalator in 90 s. 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?

30 s
45 s
60 s
90 s

Answer 1

Answer:

The correct option is B.

Explanation:

Let the length of the escalator be L.

Let the speed of the escalator be y and the man’s walking speed be x.

30 = L/(x+y)

Similarly, 90 = L/(x-y)

Dividing the two equations, you get

3 = (x+y)/(x-y)

x = 2y or y = x/2

Now, find L/x (since the escalator is not moving at all)

From the first equation, putting y = x/2, you get 30 = L/(x + x/2) = L/(3/2x)

L/x = 30 x 3/2 = 45

Answer 2

Answer:

the correct answer is 45 seva

plz mark me as brainiliest