Question

Suppose we represent the distance above the ground by a positive integer and that below ground by a negative integer then
i) An elevator descends in to a mine shaft at the rate of 7 meter per minute . What will be its position after one hour?
II) If it begins to descend from 25 m above the ground what will be its position after 45 minutes?

Answer 1

Step-by-step explanation:

Since, the elevator going down, so the distance covered by it will be represented by a negative integer.

Change in position of elevator in one minute = −5 m.

Position of the elevator after 60 minutes = (−5)×60=−300  m 

That means the position of the elevator will be 300 m below ground level.