Question

A street lane is to be paved with bricks. The length of the lane is \[240m\] and its breadth is \[12m\]. How do you find the number of bricks required to pave the lane if each brick measures \[22.5cm\] by \[10cm\]?

Answer 1

Hint: We are given the dimensions of a street lane and we are also given the dimensions of a brick. The street lane is to be paved with bricks and we are asked to find the number of bricks required to pave the lane. We will first find the area of the street lane to be paved. Then, we will find the area of a brick. We will use the formula of area of the rectangle to find the required areas. And then, we will divide the area of the street lane by the area of a brick and we will get the number of bricks required to pave the lane.

Complete step by step answer:
According to the given question, we are given that the dimension of a street lane is \[240m\] by \[12m\] and we have to pave it with bricks which are of the dimensions \[22.5cm\] by \[10cm\]. We are asked to find out the number of bricks required for paving the lane.
The street lane has the length as \[240m\] and the breadth as \[12m\], which is a rectangle.
So, we will now calculate the area of the lane and we get,
Area of the street lane = \[l\times b\]
\[\Rightarrow 240m\times 12m\]
\[\Rightarrow 2880{{m}^{2}}\]
We will now find the area of one brick, we are given the dimensions of the brick as, \[22.5cm\] by \[10cm\].
We have length as \[22.5cm=\dfrac{22.5}{100}m\]
We have the breadth as \[10cm=\dfrac{10}{100}m\]
Area of the brick = \[l\times b\]
\[\Rightarrow \dfrac{22.5}{100}\times \dfrac{10}{100}\]
\[\Rightarrow \dfrac{225}{10000}{{m}^{2}}\]
In order to find the number of bricks required, we will divide the area of the street lane by the area of one brick. So we have,
Number of bricks required = \[\dfrac{\text{Area of the lane}}{\text{Area of a brick}}\]
\[\Rightarrow \dfrac{2880}{\left( \dfrac{225}{10000} \right)}\]
\[\Rightarrow \dfrac{2880\times 10000}{225}\]
\[\Rightarrow 128000 bricks\]
Therefore, the number of bricks required is 128000 nos.

Note: We can understand the geometry of a given region by their dimensions. We have the two different values, so it was easy to see that the street lane is in the shape of a rectangle. Had it been the same values, then it would have been a square. Also, while incorporating two or more entities in an expression, we must make sure that the units used are the same or else the answer will be wrong.