The dimensions of a window are $\displaystyle 156$ cm × $\displaystyle 216$ cm. Arjun wants to put grill on the window creating complete squares of maximum size. Determine the side length of the square and hence find the number of squares formed.

\[\begin{aligned} & 156=2 \times 2 \times 3 \times 13=2^{2} \times 3 \times 13 \\ & 216=2 \times 2 \times 2 \times 3 \times 3 \times 3=2^{3} \times 3^{3} \\ & \therefore \text { Required side length of the square }=\operatorname{HCF}(156,216)=12 \mathrm{~cm} \\ & \text { Number of squares formed }=\frac{156 \times 216}{12 \times 12}=234 \end{aligned} \]