OnlyGyaani • Class 4 Learning

Class 4 Mathematics

Develop stronger mathematical reasoning through 30 structured lessons covering large numbers, four operations, factors, multiples, fractions, decimals, geometry, perimeter, measurement, time, money, graphs, tessellations and geometric patterns.

🔢 Large Numbers & Operations

Reading and Writing Five- and Six-Digit Numbers

Five- and six-digit numbers allow us to represent much larger quantities. In the Indian system, commas help us read these numbers in groups.

24,615 → twenty-four thousand six hundred fifteen

3,45,218 → three lakh forty-five thousand two hundred eighteen

9,99,999 → nine lakh ninety-nine thousand nine hundred ninety-nine

Write in numerals:
1. Seventy-two thousand three hundred fifteen = ______
2. Four lakh twenty thousand six hundred eight = ______

Five-digit numbers begin from 10,000 and six-digit numbers begin from 1,00,000.

Understanding the Indian Place Value System

The Indian place value system groups digits into ones, thousands and lakhs periods.

Lakhs	Ten Thousands	Thousands	Hundreds	Tens	Ones
4	5	2	6	3	8

4,52,638

4 lakhs = 4,00,000
5 ten-thousands = 50,000
2 thousands = 2,000
6 hundreds = 600
3 tens = 30
8 ones = 8

Find the place value of 7 in 3,72,415.

Indian commas are placed as 1,00,000 and 10,00,000 after the first three digits from the right and then every two digits.

Rounding Numbers to Nearest Tens and Hundreds

Rounding gives an approximate value that is easier to work with.

Nearest Ten

43 → 40
47 → 50
125 → 130

Nearest Hundred

241 → 200
268 → 300
750 → 800

Round:
1. 76 to the nearest ten = ___
2. 342 to the nearest hundred = ___
3. 685 to the nearest hundred = ___

For standard rounding, 0–4 round down and 5–9 round up.

Adding Large Numbers With Regrouping

Large numbers are added by arranging digits according to place value and regrouping whenever a column totals 10 or more.

24,685 + 13,749

24,685
+13,749
────────
38,434

Solve:
35,768 + 24,596 = ______
1,25,430 + 2,14,625 = ______

Keep every place-value column correctly aligned.

Subtracting Large Numbers With Regrouping

When a digit in the top number is smaller than the digit being subtracted, regroup from the place to its left.

52,463 − 27,185 = 25,278

Solve:
64,350 − 21,725 = ______
85,000 − 36,458 = ______

You can check subtraction by adding the difference and the subtracted number.

Multiplying Three-Digit Numbers

Three-digit numbers can be multiplied using place-value strategies or the standard written method.

324 × 6

300 × 6 = 1,800
20 × 6 = 120
4 × 6 = 24

1,800 + 120 + 24 = 1,944

125 × 24

125 × 20 = 2,500
125 × 4 = 500
Total = 3,000

213 × 4 = ___
325 × 12 = ___

Dividing Large Numbers by One-Digit Divisors

Long division allows us to divide larger numbers step by step.

936 ÷ 3

9 ÷ 3 = 3
3 ÷ 3 = 1
6 ÷ 3 = 2

936 ÷ 3 = 312

1,248 ÷ 4 = 312

848 ÷ 4 = ___
1,575 ÷ 5 = ___

Check division using:
Divisor × Quotient + Remainder = Dividend

Solving Complex Four-Operation Word Problems

Some problems require addition, subtraction, multiplication or division, and sometimes more than one operation.

A school buys 8 boxes containing 25 notebooks each.

8 × 25 = 200 notebooks.

It gives 65 notebooks to students.

200 − 65 = 135 notebooks remaining.

A shop has 12 boxes with 30 pencils in each box. It sells 145 pencils. How many pencils remain?

Read the entire problem, identify the quantities and decide the order of steps before calculating.

🔍 Factors & Multiples

Identifying Factors of Whole Numbers

A factor divides a whole number exactly without leaving a remainder.

Factors of 12:

1 × 12
2 × 6
3 × 4

Therefore:
1, 2, 3, 4, 6, 12

Find all factors of:
10
18
20

1 and the number itself are always factors of a positive whole number.

Finding Multiples of Whole Numbers

Multiples are produced by multiplying a number by whole numbers.

Multiples of 4:
4, 8, 12, 16, 20, 24…

Multiples of 7:
7, 14, 21, 28, 35…

Write the first six positive multiples of:
5
8

Multiples continue without end.

Recognising Common Factors and Common Multiples

Common factors are factors shared by two or more numbers. Common multiples are multiples shared by two or more numbers.

Factors of 12: 1, 2, 3, 4, 6, 12
Factors of 18: 1, 2, 3, 6, 9, 18

Common factors = 1, 2, 3, 6

Multiples of 4: 4, 8, 12, 16, 20, 24…
Multiples of 6: 6, 12, 18, 24, 30…

Common multiples include 12, 24…

Find the common factors of 8 and 12.

🍕 Fractions & Decimals

Understanding Equivalent Fractions

Equivalent fractions look different but represent the same value.

1/2 = 2/4 = 3/6

2/3 = 4/6

We can create equivalent fractions by multiplying the numerator and denominator by the same non-zero whole number.

Complete:
1/3 = ___/6
2/5 = 4/___

Multiplying or dividing the numerator and denominator by the same non-zero number keeps the fraction’s value unchanged.

Comparing Like and Unlike Fractions

Like fractions have the same denominator. Unlike fractions have different denominators.

Like fractions:
5/8 > 3/8

Unlike fractions:
1/2 and 2/3

1/2 = 3/6
2/3 = 4/6

Therefore, 2/3 > 1/2.

Compare using >, < or =:
4/7 ___ 2/7
1/2 ___ 3/4

Adding Fractions With Like Denominators

When fractions have the same denominator, add their numerators and keep the denominator unchanged.

2/7 + 3/7 = 5/7

1/8 + 4/8 = 5/8

2/9 + 5/9 = ___
3/10 + 4/10 = ___

For like fractions, the equal-sized parts do not change, so the denominator stays the same.

Subtracting Fractions With Like Denominators

When denominators are the same, subtract the numerators and keep the common denominator.

6/8 − 3/8 = 3/8

7/10 − 2/10 = 5/10 = 1/2

8/9 − 3/9 = ___
7/12 − 4/12 = ___

Introduction to Decimal Numbers

Decimals are another way of representing parts of a whole. A decimal point separates the whole-number part from the fractional part.

0.5 = five tenths = 5/10 = 1/2

1.5 = one whole and five tenths

2.25 = two wholes and twenty-five hundredths

Write as decimals:
3/10 = ___
7/10 = ___
25/100 = ___

The first place to the right of the decimal point is the tenths place.

Understanding Tenths and Hundredths

Decimals use place value just like whole numbers. Positions to the right of the decimal point represent fractional values.

Ones	.	Tenths	Hundredths
4	.	7	2

4.72

4 = 4 ones
7 = 7 tenths
2 = 2 hundredths

0.1 = 1/10
0.01 = 1/100
0.25 = 25/100

In 6.38:
What digit is in the tenths place?
What digit is in the hundredths place?

📐 Geometry

Classifying Lines, Rays and Line Segments

Lines, rays and line segments differ according to whether they have endpoints.

Line: extends endlessly in both directions.

Ray: begins at one endpoint and continues endlessly in one direction.

Line segment: has two endpoints.

Draw:
1. Line AB
2. Ray CD
3. Line segment EF

A line has no endpoints, a ray has one endpoint, and a line segment has two endpoints.

Measuring and Comparing Angles

Angles measure the amount of turn between two rays. Angles are measured in degrees (°).

Acute angle: less than 90°
Right angle: exactly 90°
Obtuse angle: greater than 90° but less than 180°
Straight angle: 180°

A protractor can be used to measure an angle accurately.

Classify:
45° = ______ angle
90° = ______ angle
120° = ______ angle

Classifying Triangles by Sides

Triangles can be classified according to the lengths of their sides.

Equilateral triangle: 3 equal sides
Isosceles triangle: 2 equal sides
Scalene triangle: all sides have different lengths

Classify a triangle with sides:
5 cm, 5 cm, 5 cm = ______
4 cm, 4 cm, 6 cm = ______
3 cm, 4 cm, 5 cm = ______

Exploring Quadrilaterals and Their Properties

A quadrilateral is a polygon with four sides, four vertices and four angles.

Square: 4 equal sides and 4 right angles

Rectangle: opposite sides equal and 4 right angles

Rhombus: 4 equal sides

Parallelogram: both pairs of opposite sides are parallel

Trapezium: has at least one pair of parallel sides in the commonly used school definition

Which quadrilateral has four equal sides and four right angles?

Understanding Lines of Symmetry

A line of symmetry divides a shape into two matching mirror-image halves.

Square: 4 lines of symmetry
Rectangle: 2 lines of symmetry
Equilateral triangle: 3 lines of symmetry

Draw a square and mark all its lines of symmetry.

The two parts on opposite sides of a line of symmetry must match when reflected.

Calculating Perimeter of Regular Shapes

Perimeter is the total distance around the boundary of a closed shape. For a regular polygon, all sides have equal length.

A square has side length 6 cm.

Perimeter = 6 + 6 + 6 + 6
= 24 cm

A regular pentagon has sides of 4 cm each.

Perimeter = 5 × 4
= 20 cm

Find the perimeter of an equilateral triangle with each side measuring 7 cm.

Perimeter is measured in units of length such as cm or m.

📏 Measurement & Time

Converting Units of Length

Different standard units are used for different lengths.

1 kilometre = 1000 metres
1 metre = 100 centimetres
1 centimetre = 10 millimetres

3 m = 300 cm
5 km = 5000 m
250 cm = 2 m 50 cm

Convert:
7 m = ___ cm
4 km = ___ m
350 cm = ___ m ___ cm

Converting Units of Mass and Capacity

Mass and capacity can be expressed using related standard units.

Mass

1 kilogram = 1000 grams
3 kg = 3000 g
2 kg 500 g = 2500 g

Capacity

1 litre = 1000 millilitres
4 L = 4000 mL
2 L 250 mL = 2250 mL

5 kg = ___ g
3500 g = ___ kg ___ g
6 L = ___ mL
4250 mL = ___ L ___ mL

Reading Time Using 12-Hour and 24-Hour Clocks

The 12-hour clock uses a.m. and p.m. The 24-hour clock numbers the hours from 00 to 23.

7:00 a.m. → 07:00
1:00 p.m. → 13:00
4:30 p.m. → 16:30
9:15 p.m. → 21:15

Convert to 24-hour time:
3:20 p.m. = ______
8:45 p.m. = ______

Convert to 12-hour time:
14:30 = ______
19:15 = ______

For typical p.m. times from 1 p.m. to 11 p.m., add 12 to the hour when converting to 24-hour time.

Calculating Elapsed Time

Elapsed time is the amount of time that passes between a starting time and an ending time.

A film begins at 2:30 p.m. and finishes at 4:15 p.m.

2:30 → 3:30 = 1 hour
3:30 → 4:15 = 45 minutes

Elapsed time = 1 hour 45 minutes

A school event begins at 9:20 a.m. and ends at 11:05 a.m.
Find the elapsed time.

Breaking the time interval into smaller parts can make elapsed-time problems easier.

💰 Money, Data & Patterns

Solving Bills and Money Transactions

Bills show the prices and quantities of items purchased. We can use addition and subtraction to calculate totals and change.

Item	Quantity	Price Each	Amount
Notebook	2	₹45	₹90
Pen	3	₹20	₹60
Total			₹150

If the customer pays ₹200:

Change = ₹200 − ₹150
= ₹50

A student buys:
2 books at ₹75 each
1 pencil box for ₹80

Find the total bill.
If ₹300 is paid, find the change.

Constructing and Interpreting Bar Graphs

A bar graph represents data using rectangular bars. The scale tells us how much each unit of bar length represents.

Books Read in One Month

Aman    ████ 4
Riya     ███████ 7
Neha    █████ 5
Kabir   ██████ 6

From the graph, Riya read the most books and Aman read the fewest.

Using the graph above:
1. How many books did Kabir read?
2. How many more books did Riya read than Aman?
3. How many books did all four students read altogether?

Constructing a Bar Graph

To construct a bar graph, choose categories, select a suitable scale, label the axes and draw equal-width bars with appropriate heights.

Always read the title, labels and scale before interpreting a bar graph.

Exploring Tessellations and Geometric Patterns

A tessellation is a repeating arrangement of shapes that covers a surface without gaps or overlaps.

Squares can tessellate:

■ ■ ■ ■
■ ■ ■ ■
■ ■ ■ ■

Equilateral triangles and regular hexagons can also form regular tessellations.

Geometric Patterns

▲ ■ ● ▲ ■ ● ▲ ■ ●

The repeating unit is:
▲ ■ ●

1. Draw a tessellation using squares.
2. Create a repeating pattern using three different shapes.
3. Identify the repeating unit in your pattern.

A tessellation covers a surface with no gaps and no overlapping shapes.