**Pre-Requisites**

- Basic understanding of figures

## Learning Objective

On successful completion of this lesson, students will be able to:

- demonstrate basic knowledge of solids, volume..
- analyze how to find volume of cube & cuboid.
- develop problem-solving skills.
- apply in real life.

**Dictionary**

- Solid: Form of matter
- Volume: Occupied space
**Picture**: Figure**Graph**: Grapgh or Sketch**Percentage**: %age**Average**: Mean**Numeral**: Number**>**: Greater than**<**: Lesser than**=**: Equal to**Ascending**: Increasing**Descending**: Decreasing**Order**: Sequence

**23.1 Introduction**

#### 23.1.1 Solid

=> **Solid**: An object having definite shape & size is called solid.

=> Solids are occur in different **shapes** & **sizes**.

=> Some of solids are:

- Cube
- Cuboid
- Cone
- Cylinder
- Sphere

#### 23.1.2 Volume

=> **Volume**: Solids occupy a certain amount of **space** called volume.

#### 23.1.3 Units of Volume

**Cubic centimetre**: The volume of a cube of edge 1 cm, is called 1 cubic centimetre.

=> It is denoted by **1 cu cm** or **1cm³**.

2. **Cubic metre**: The volume of a cube of edge 1 m, is called 1 cubic metre.

=> It is denoted by **1 cu m** or **1 m³**.

**23.2 Cuboid**

=> **Cuboid**: A solid bounded by six rectangular faces is called a cuboid.

e.g a **brick** , a match box, a paste box, a chalk box, a book etc.

#### 23.2.1 Volume of a cuboid

#### Formula

**V= (l x b x h) m³**

Where l = length, b= breadth, h= height

**23.3 Cube**

=> **Cube**: A cuboid whose length , breadth & height are equal , is called a cube.

e.g a **dice**, an ice cube, a sugar cube etc.

#### 23.3.1 Volume of a cube

#### Formula

**V = (a x a x a) m³**

Where a = side

#### Solved Examples

**Ex1. The length , breadth and height of a cuboid are 10 cm, 5 cm amd 2 cm respectively. Find its volume.**

**Sol**. Given that:

l= 10 cm

b= 5 cm

h= 2 cm

V=l x b x h = 10 cm x 5 cm x 2 cm = 100 cm³

V= 100 cu cm.

**Ex2. Find the volume of a cube whose each edge is 2 cm.**

**Sol**. Given that:

a= 2 cm

V= a x a x a = 2x2x2 = 8 cu cm

**Ex3. How many bricks each 24 cm long, 12.5 cm wideand 8 cm thick will be required to build a wall 18 m long, 2.5 m high and 40 cm thick?**

**Sol**. Lenght of the wall = 18 m= 1800 cm

Height oof the wall = 2.5 m = 250 cm

Thickness oof the wall = 40 cm

Volume of the wall = l x b x h = (1800 x 250 x 40 ) cu cm

Now,

Length of a brick = 24 cm

Breadth of the brick = 12.5 cm

Thickness oof the brick = 8 cm

v = (24 x 12.5 x 8) cu cm

Therefore, The number of bricks required = V/v = (1800 x 250 x40) / (24 x 12.5 x 8)

= 7500 ans.

**23.4 Practice Sets **

- Fill Type
- Match Type
- Order Type
- Conversion Type
- Compare Type
- Error Type
- Statement Type
- True/False Type
- Related Type
- Day-to-Day Type
- Miscellaneous Type

#### Set-1

1.Express each of the following as a fraction in its lowest terms.

**2. **Express each of the following as a decimal.

3. Convert each of the following fractions into a percentage.

4.Convert each of the following decimals into percentage.

5. Find the value of

**6. Which of the following are meaningless?**

**7. Compare and put symbol >, < or =in the placeholder.**

**8. Fill in the blanks.**

**9. Cross (x) the Roman numerals which are not written correctly.**

**10. Write the following Roman numerals in ascending order.**

**11. Write the following Roman numerals in descending order.**

**12. Solve & write the answer in Roman numerals.**

**13. Complete the following table.**

#### Set-2

#### Set-3

#### Set-4

#### Set-5

**23.5 Quiz**

**23.6 Test**

**23.7 Exam**

The exam will be conducted after the completion of the course.

**23.8 Ask Question**

Ask your doubts **here**

#### …..The End…..

**Other Notes**

- Counting from one to hundred: एक से लेकर सौ तक गिनती
- Punctuation Mark: विराम चिन्ह
- Roman Numerals : 1 to 3000
- Testing
- Words Start with letter G
- Words Start with letter F
- Words Start with letter E
- Words Start with letter D
- Words Start with letter C
- Words Start with letter B