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?

To solve this problem, we use the Chain Rule formula for work, which states that the relationship between men (M), days (D), and work (W) is:{M_1 x  D_1} \{W_1} = {M_2 x D_2} \ {W_2}