Question:
A pit 5 m long and 3.5 m wide is dug to a certain depth. If the volume of earth taken out of it is 14 m3, what is the depth of the pit?
Solution:
Let the depth of the pit be $d \mathrm{~m}$.
Volume $=$ Length $\times$ width $\times$ depth $=5 \mathrm{~m} \times 3.5 \mathrm{~m} \times d m$
But,
Given volume $=14 \mathrm{~m}^{3}$
$\therefore$ Depth $=d=\frac{\text { volume }}{\text { length } \times \text { width }}=\frac{14}{5 \times 3.5}=0.8 \mathrm{~m}=80 \mathrm{~cm}$