Lesson eLearning

An elevator descends into a mine shaft at the rate of . If the descent starts from above the ground level, how long will it take to reach a depth of ?

hard 4 marks Class 7 · Mathematics · Integers
Answer

The correct answer is — Calculate the time taken by dividing the total distance by the rate of descent: .

Step-by-step solution

  1. Determine the initial position of the elevator relative to ground level: .
  2. Determine the final position of the elevator: .
  3. Calculate the total distance to be descended: Total distance = Initial position - Final position = .
  4. Determine the rate of descent: .
  5. Calculate the time taken by dividing the total distance by the rate of descent: .
Common mistake: Students often calculate the distance as by ignoring the fact that descent starts above the ground level.

Concept tested: Subtraction and division of integers in context of height and depth

Published · How this solution was prepared and checked

Related questions

← All Integers questions