Question

How many bricks of dimensions 22cm x 10cm x 7cm are required to construct a wall 33m long, 3.5m high, and 40cm thick, if cement and sand used in construction occupy 1/10 of the wall.

Answer 1

The number of bricks required is 27,000.

Step-by-step explanation:

We have to find the number of bricks of dimensions 22 cm x 10 cm x 7 cm required to construct a wall 33 m long, 3.5 m high, and 40 cm thick if cement and sand used in construction occupy (1/10) of the wall.

As we know that the volume of the cuboid is given by = Length $\times$ Breadth $\times$ Height.

So, the volume of the wall = 33 m $\times$ 3.5 m $\times$ 40 cm

                                            = (33 $\times$ 100) cm $\times$ (3.5 $\times$ 100) cm $\times$ 40 cm

                                            = 3300 cm $\times$ 350 cm $\times$ 40 cm

                                            = 46200000 $\text{cm}^{3}$.

Now, it is stated that the cement and sand used in construction occupy (1/10) of the wall.

So, the actual volume of the wall = Volume of the wall - ( $\frac{1}{10}$ $\times$ Volume of the wall)

                              = $46200000 - (\frac{1}{10} \times 46200000)$

                              = 46200000 - 4620000

                              = 41580000 $\text{cm}^{3}$

Now, the volume of one brick = 22 cm $\times$ 10 cm $\times$ 7 cm

                                                  = 1540 $\text{cm}^{3}$

So, the number of bricks required = $\frac{\text{Actual volume of wall}}{\text{Volume of one brick}}$

                                                         = $\frac{41580000}{1540}$

                                                         = 27,000 bricks.

Hence, the number of bricks required is 27,000.