Question

How many bricks each $24$cm long,$12.5$cm wide and $8$cm thick will be required to build a wall $18$m long,$2.5$m high and $40$cm thick?

Answer 1

Length of the wall$=18$m$=1800$cm

Height of the wall$=2.5$m$=250$cm

Thickness of the wall$=40$cm

Volume of the wall$=length\times height\times thickness$cubic units.

$=1800\times 250\times 40$cu.cm

Length of the brick$=24$cm

Height of the brick$=12.5$cm

Thickness of the brick$=8$cm

Volume of the brick$=length\times height\times thickness$cubic units.

$=24\times 12.5\times 8$cu.cm

$\therefore$the number of bricks required$=\frac{volumeofthewall}{volumeof1brick}$

$=\frac{1800\times 250\times 40}{24\times 12.5\times 8}$

$=\frac{1800\times 250\times 40\times 10}{24\times 125\times 8}$

$=1800\times 2\times 5\times 5=7500$

Hence , the number of bricks required$=7500$