Question

The paint in a certain container is sufficient to paint on area equal to 9.375$m^2$. How many bricks of dimension 22.5 $cm\times 10cm\times 7.5cm\text{can be painted out of this container?}$

Answer 1

$\text{Area that can be painted}=9.375m^2$

$\text{Dimension of one brick}=22.5cm\times 10$$cm\times 7.5cm$

$\therefore \text{Surface area of one brick}$ $=2(lb+bh+hl)$

$=2[22.5\times 10+10\times 7.5+7.5\times 22.5]c{m}^2$

$=2[225+75+168.75]$

$=2\times 468.75c{m}^2=937.5c{m}^2$

$\therefore \text{Number of bricks}=\frac{\text{Total area}}{\text{Area of one brick}}$

$=\frac{9.375\times 100\times 100}{937.5}$

$=\frac{937.5\times 100}{937.5}=100bricks$