The volume of a cuboidal box is 48 cm³. If its height and length are 3 cm and 4 cm respectively, find its breadth.

$$\begin{gathered} \mathrm{Suppose}\mathrm{that}\mathrm{the}\mathrm{breadth}\mathrm{of}\mathrm{the}\mathrm{box}\mathrm{is}b\mathrm{cm}. \\ \mathrm{Volume}\mathrm{of}\mathrm{the}\mathrm{cuboidal}\mathrm{box}=48{\mathrm{cm}}^3 \\ \mathrm{Height}\mathrm{of}\mathrm{the}\mathrm{box}=3\mathrm{cm} \\ \mathrm{Length}\mathrm{of}\mathrm{the}\mathrm{box}=4\mathrm{cm} \\ \mathrm{Now},\mathrm{volume}\mathrm{of}\mathrm{box}=\mathrm{length}\times \mathrm{breadth}\times \mathrm{height} \\ \Rightarrow 48=4\times b\times 3 \\ \Rightarrow 48=12\times b \\ \Rightarrow b=\frac{48}{12}=4\mathrm{cm} \\ \therefore \mathrm{The}\mathrm{breadth}\mathrm{of}\mathrm{the}\mathrm{cuboidal}\mathrm{box}\mathrm{is}4\mathrm{cm}. \end{gathered}$$