Question

$\Large\underline{\underline{\pmb{\sf{\bigstar \; Questiion \; ;}}}}$

How many bricks of length 25cm, breadth 15cm and height 10cm are required to build a wall of length 6m, height 2.5m and breadth 0.5m?


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The answer ;; 2000 bricks will be needed to build the wall.
I wanna know how to solve this one.
– Well explained answer please! :^)~

Answer 1

I'm pretty sure you don't have any issue with the formula part of this question,the only issue might be in deciding what are we supposed to do with the volume of brick and the volume of wall and which algebraic operation is actually needed to find the number of bricks (let's call it x).

So,first things first, let's us find the volume of the brick. Now maybe,just maybe you might think why are we talking about volume and not about any other quantity like perimeter, surface area etc etc. Well, let's discuss it a bit about each.

Suppose you decide to find the perimeter of the brick (cuboid). So, calculating perimeter will only give you the sum of the dimensions of the brick but of a brick isn't hollow from inside, so it will be a great error in the planning of the house xD

Now, talking about area (by area I'm including every possible area available for a cuboid because discussing them individually is not a very sensible task). So,area will again only give you the space the brick will occupy if you keep it at certain place. But then we only will be able to know about the surface the brick will cover and not about anything else, like imagine x-y axis, you will only be able to know about them however our real world is a 3 dimensional world,so missing out z axis with each brick is going to be a blunder once again. So,now let's come to volume which actually refers to the capacity of any object,by capacity we are assured that the perimeter as well as area is taken into account because for sure if you are able to find the capacity of certain object,the area and perimeter is associated to it by default.

So,i don't know how else to explain you this xD thats all, let me move towards the question.

Calculating the volume of the brick :

Vbrick = l × b × h

Put the values,

Vbrick = 25 × 15 × 10

Vbrick = 250 × 15

Vbrick = 250 × (10 + 5)

Vbrick = 2500 + 1250

Vbrick = 3750 cm³

Now, calculating the volume of the wall,

Vwall = l × b × h

Vwall = 6 × 2.5 × 0.5

Vwall = 6 × 1.25

Vwall = 7.5 m³

Vwall = 7500000cm³

(why did we convert the units? because it's always better to play with smaller units)

Now,see the volume we have calculated is of one single brick and we also know the volume of the wall,so 1 brick's volume is known, multiply by that volume by x (number of bricks required) and the product of the two will of course leave you with your wall prepared.

So, number of bricks,

x × (3750) = 7500000

x = 7500000/3750

x = 2000

∴ 2000 bricks will be required to build that wall.

Answer 2

length of brick = 25cm

breadth of brick = 15 cm

height of brick = 10cm

volume of brick = length × breadth × height

= 25 cm × 15 cm × 10cm

= 3750 cm³

length of wall = 6m = 600 cm

breadth of wall = 0.5 m = 50cm

height of wall = 2.5 m = 250 cm

volume of wall = length × breadth × height

= 600 × 250 × 50 = 7500000 cm³

number of bricks= volume of wall/volume of brick

= 7500000/3750

= 750000/375

= 2000

hence, number of bricks = 2000

hii how are you :)