Question:
A 36 m-long, 15 broad verandah is to be paved with stones, each measuring 6 dm by 5 cm. How many stones will be required?
Solution:
Area of the verandah $=$ Length $\times$ Breadth $=36 \times 15=540 \mathrm{~m}^{2}$
Length of the stone = 6 dm = 0.6 m
Breadth of the stone = 5 dm = 0.5 m
Area of one stone $=0.6 \times 0.5=0.3 \mathrm{~m}^{2}$
Number of stones required $=\frac{\text { Area of the verendah }}{\text { Area of the stone }}$
$=\frac{540}{0.3}$
$=1800$
Thus, 1800 stones will be required to pave the verandah.