Question

Suppose we represent the distance above the ground by a positive integer and below the
ground by a negative integer. An elevator descends into a mine shaft at 3m per minute. If it
begins to descend from 12m above the ground, what will be its position after 12 minutes?
What distance would it have travelled?​

Answer 1

Above the Ground = +ve integer

Below the Ground = -ve integer

Rate of Motion = 3m/min

12m above the ground so,

Position in 12 min = 12 x 3 = 36 m

Since it is said the elevator descends, the figure will be -36m

It began 12 m above the ground, so the final distance travelled will be

(-36-12)m = (-48)m