Question

Question 7
An elevator descends into a mineshaft at the rate of 6 m/min. If the descent starts from 10 m above the ground level, how long will it take to reach -350 m.

Answer 1

Distance descended is denoted by a negative integer.
Initial height = +10 m
Final depth= - 350 m
Total distance to be descended by the elevator = (- 350) - (+10) = -360 m
Time taken by the elevator to descend - 6 m = 1 min
Thus, time taken by the elevator to descend - 360 m = (- 360) $÷$ (-6)
= 60 minutes = 1 hour