Question

How many bricks, each measuring 25 cm $\times$ 11.25 cm $\times$ 6 cm, will be needed to build a wall 8 m long, 6 m high and 22.5 cm thick?

(a) 5600

(b) 6000

(c) 6400

(d) 7200

Answer 1

Length of wall (l)=8 m =800 cm

Breadth (b)=22.5 cm

Height (h)=6 m =600 cm

$\therefore$ Volume of wall $=l\times b\times h=800\times 22.5\times 600c{m}^3$

$=10800000c{m}^3$

Volume of one brick $=25\times 11.25\times 6c{m}^3$

$=1687.5c{m}^3$

$\therefore$ Number of bricks required

$=\frac{10800000}{1687.5}=6400$