Question

How many bricks, each measuring (25 cm × 11.25 cm × 6 cm), will be required to construct a wall (8 m × 6 m × 22.5 cm)?
(a) 8000
(b) 6400
(c) 4800
(d) 7200

Answer 1

(b) 6400

Volume of the wall$=\left(800\times 600\times 22.5\right){\text{cm}}^3$
Volume of each brick = $\left(25\times 11.25\times 6\right){\mathrm{cm}}^3$

Number of bricks$=\frac{\text{Volume of the wall}}{\text{Volume of each brick}}$

$$\begin{gathered} =\frac{800\times 600\times 22.5}{25\times 11.25\times 6} \\ =6400 \end{gathered}$$