The floor of a rectangular hall is 24 m long and 18 m wide. How many carpets, each of length 2.5 m and breadth 80 cm, will be required to cover the floor of the hall?

Length of hall $=24m$
Breadth of hall $=18m$
Length of carpet $=2.5m$
Breadth of carpet $=80cm=0.8m$
Area of hall $=Length\times Breadth$
                    $=24\times 18$
                    $=432m^2$
And, Area of carpet $=Length\times Breadth$
                                  $=2.5\times 0.8$
                                  $=2m^2$
Number of carpets $=$ $\frac{\text{(area of hall)}}{\text{(Area of carpet)}}$ $=\frac{432}{2}=216$
That is, number of carpets are 216.