2)Paul walks up a moving-up escalator.Find the number of steps in the
escalator and the speed of the escalator in steps per second
with the following conditions:
a)If he takes 2 steps per second , he will reach the top after taking 32
steps.
b)If he takes only 1 step per second , he will reach the top after
taking 20 steps.
Let x be the number of steps,and y steps per second be the speed
of the escalator.
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