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A person walks up a stalled escalator in...

A person walks up a stalled escalator in 90 s. When standingon the same escalator, now moving, he is carried in 60 s.The time it would take him to walk up the moving escalator will be:

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The correct Answer is:
3
By observation, for equal interval of time the magnitude of slope of line in x-t curve is greatest in interval 3.
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Knowledge Check

  • At a metro station, a girl walks up a stationary escalator in time. t _(1), If she remains stationary on the escalator, then the escalator take her up in time t_(2). The time taken by her to walk up on the moving escalator will be

    A
    `(t_(1) +t_(2)) //2`
    B
    `t _(1) t _(2) // (t - t _(1))`
    C
    `t _(1) t _(2) //(t_(2) + t _(1))`
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    `t _(1) - t _(2)`

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