Question

How many bricks each 25 cm long, 16 cm wide and 7.5 cm thick, will be required to build a
terrace 5 m long, 3 m broad and 80 cm high?​

Answer 1

Volume of brick = 25×15×6=2250 cm3

Volume of wall = 5×200×50=50000 cm3

10 % of volume of wall is occupied by cement, therefore, volume of wall left for bricks is :

=50000−10010​×50000=50000−5000=45000 cm3

Hence,

Number of bricks required = 225045000​=20

Answer 2

Hi there!

Here is your answer -

BRICK

Length = 25cm

Width = 16cm

Thick = 7.5cm

Area of brick = l×b×t

= 25×16×7.5

= 3000 cm^2

TERRACE

Length = 5m = 500cm

Breadth = 3m = 300cm

Height = 80cm

Area of terrace = l×b×h

= 500×300×80

= 12000000cm^2

So,

Number of bricks required to built the terrace

= Area of terrace/ area of brick

= 12000000 / 3000

= 4000

Hence, 4000 bricks required to built the terrace.