Question

If 20 men can build a wall 56 metres long in 6 days, what length of a similar wall can be built by 35 men in 3 days?

• A. 36 metres
• B. 25 metres
• C. 49 metres
• D. 50 metres

Hint:

- In work-related problems, use the formula \( \text{Work} = \text{Men} \times \text{Days} \) to find the proportional relationship between men, days, and the work done.

Answer 1

The Correct Option is C

Step 1: Understanding the Given Data
We know that 20 men can build a 56-metre long wall in 6 days. We are asked to find how much of a similar wall 35 men can build in 3 days. This is a problem of work and man-days. Step 2: Work Calculation
The total work done is proportional to the number of men and the number of days worked. Let the length of the wall built by 35 men in 3 days be \( L \). The relationship is given by: \[ \text{Work} = \text{Number of men} \times \text{Number of days} \] For the first case: \[ 20 \times 6 = 120 \quad \text{man-days of work to build 56 metres} \] For the second case: \[ 35 \times 3 = 105 \quad \text{man-days of work} \] The amount of work done in the second case is \( \frac{105}{120} \) of the work done in the first case, so the length of the wall built is: \[ L = \frac{105}{120} \times 56 = 49 \text{ metres} \] Thus, the length of the wall built by 35 men in 3 days is 49 metres. Therefore, the correct answer is (3) 49 metres.