Question

Question 4
The paint in a certain container is sufficient to paint an area equal to $9.375m^2$. How many bricks of dimensions $22.5cm\times 10cm\times 7.5cm$ can be painted out of this container?

Answer 1

Total surface area of one brick = 2(lb + bh +hl)
$=\left[2\right(22.5\times 10+10\times 7.5+22.5\times 7.5\left)\right]c{m}^2$
$=2(225+75+168.75)c{m}^2$
$=(2\times 468.75)c{m}^2$
$=937.5c{m}^2$

Let n bricks can be painted by the paint of the container.
Area of n bricks
$=(n\times 937.5)c{m}^2=937.5nc{m}^2$
Area that can be painted by the paint of the container
$=9.375m^2=93750c{m}^2$
$\therefore 93750=937.5n$
So, n = 100

Therefore, 100 bricks can be painted out by the paint of the container.