Question

Question 11
A mason constructs a wall of dimensions 270 cm×300 cm× with the bricks each of size $22.5cm\times 11.25cm\times 8.75cm$ and it is assumed that $\frac{1}{8}$ space is covered by the mortar. Then, the number of bricks used to construct the wall is Thinking process If we divide the volume of the wall except the volume of mortar are used on wall by the volume of one brick, then we get the required number of bricks used to construct the wall.
(A) 11100
(B) 11200
(C) 11000
(D) 11300

Answer 1

Option (B) is correct.
Volume of the wall $=270\times 300\times 350=28350000c{m}^3$ [ Volume of cuboid $=length\times breadth\times height]$
Since, $\frac{1}{8}$ space of wall is covered by mortar.
$=28350000–28350000\times \frac{1}{8}$
$=28350000–3543750=24806250c{m}^3$
Now, volume of one brick $=22.5\times 1125\times 8.75=2214.8044c{m}^3$
$\therefore$ Required number of bricks $=\frac{24806250}{2214.844}=11200\left(approx\right)$