Maths

Ordering Numbers

Class 3 | Comparing and Arranging Numbers

🎯 Learning Objectives

📖 Introduction

In a cricket match, India scored 287 runs and Australia scored 264 runs. Which team scored more? To answer this, we need to compare the two numbers. Comparing and ordering numbers is something we do every day — checking prices at a shop, reading cricket scores, or finding which city has more people!

In this chapter, we will learn how to compare 3-digit and 4-digit numbers, arrange them from smallest to largest (ascending order) and largest to smallest (descending order), and even form the biggest and smallest numbers from given digits.

Understanding Comparison Symbols

We use three special symbols to compare numbers:

SymbolNameMeaningExample
>Greater thanThe number on the left is bigger56 > 34
<Less thanThe number on the left is smaller23 < 45
=Equal toBoth numbers are the same50 = 50
🐊 The Crocodile Rule: Think of the > and < signs as a crocodile's mouth. The crocodile is greedy — its mouth always opens towards the bigger number! So 8 > 3 means the mouth opens towards 8 (the bigger number).

Image: The Crocodile Rule

Crocodile mouth showing greater than and less than symbols — mouth opens towards bigger number

Comparing 3-Digit Numbers

To compare two 3-digit numbers, we check the digits from left to right:

Step 1: Compare the hundreds digit first. The number with the bigger hundreds digit is greater.

Step 2: If the hundreds digits are the same, compare the tens digit.

Step 3: If the tens digits are also the same, compare the ones digit.

Example 1
Compare 547 and 382
Hundreds: 5 > 3 → So 547 > 382
(We don't need to check tens or ones because hundreds are already different.)
Example 2
Compare 463 and 489
Hundreds: 4 = 4 (same, move to tens)
Tens: 6 < 8 → So 463 < 489
Example 3
Compare 725 and 723
Hundreds: 7 = 7 (same)
Tens: 2 = 2 (same)
Ones: 5 > 3 → So 725 > 723

Comparing 4-Digit Numbers

For 4-digit numbers, we follow the same rule — compare from left to right:

Step 1: Compare the thousands digit first.

Step 2: If thousands are the same, compare hundreds.

Step 3: If hundreds are the same, compare tens.

Step 4: If tens are the same, compare ones.

Example 1
Compare 3,456 and 2,789
Thousands: 3 > 2 → So 3,456 > 2,789
Example 2
Compare 5,230 and 5,280
Thousands: 5 = 5 (same)
Hundreds: 2 = 2 (same)
Tens: 3 < 8 → So 5,230 < 5,280
💡 Quick Rule: A 4-digit number is ALWAYS greater than a 3-digit number. For example, 1,000 > 999. The number with more digits wins!
Real-Life Example
Cricket Scores: In a match, India scored 3,245 runs in a series and England scored 3,198 runs. Who scored more?
Thousands: 3 = 3 (same)
Hundreds: 2 = 1? No! 2 > 1 → India scored more! 3,245 > 3,198

Ascending Order (Smallest to Largest)

When we arrange numbers from the smallest to the largest, it is called ascending order. Think of it as climbing up a staircase — each step is higher than the last.

We use the symbol < between numbers in ascending order.

Example 1
Arrange in ascending order: 456, 231, 789, 102
Compare all: 102 is smallest, then 231, then 456, then 789.
Answer: 102 < 231 < 456 < 789
Example 2
Arrange in ascending order: 2,450, 1,890, 3,100, 2,200
Compare thousands first: 1,890 (1 thousand) is smallest.
Then 2,200 and 2,450 (both 2 thousand — compare hundreds: 2 < 4).
Then 3,100 is largest.
Answer: 1,890 < 2,200 < 2,450 < 3,100
Indian Context
Prices at a shop: A bicycle costs ₹3,500, a cricket bat costs ₹1,200, a football costs ₹850, and a badminton racket costs ₹2,100. Arrange the prices in ascending order.
Answer: ₹850 < ₹1,200 < ₹2,100 < ₹3,500

Descending Order (Largest to Smallest)

When we arrange numbers from the largest to the smallest, it is called descending order. Think of it as coming down a staircase — each step is lower than the last.

We use the symbol > between numbers in descending order.

Example 1
Arrange in descending order: 345, 678, 123, 890
Answer: 890 > 678 > 345 > 123
Example 2
Arrange in descending order: 4,500, 2,300, 6,100, 1,800
Answer: 6,100 > 4,500 > 2,300 > 1,800
Indian Context
City populations (in thousands): Jaipur has 3,046 thousand people, Lucknow has 2,817 thousand, Patna has 2,049 thousand, and Bhopal has 1,798 thousand. Arrange in descending order.
Answer: 3,046 > 2,817 > 2,049 > 1,798 (Jaipur > Lucknow > Patna > Bhopal)

Image: Ascending and Descending Order

Child arranging number cards in ascending and descending order

How to Compare Step by Step

Here is a simple method to compare any two numbers:

StepWhat to DoExample: 4,356 vs 4,329
1Count the digits. More digits = greater number.Both have 4 digits. Move to step 2.
2Compare thousands place.4 = 4. Move to step 3.
3Compare hundreds place.3 = 3. Move to step 4.
4Compare tens place.5 > 2. So 4,356 > 4,329 ✓

Forming the Greatest and Smallest Numbers

Given a set of digits, we can form the greatest and smallest possible numbers.

Rules for Forming the Greatest Number:

Arrange the digits from largest to smallest (left to right).

Rules for Forming the Smallest Number:

Arrange the digits from smallest to largest (left to right).

Special Rule: If one of the digits is 0, it cannot be the first digit (because a number doesn't start with 0). Put the next smallest digit first, then place 0 after it.

Example 1
Digits: 5, 3, 8
Greatest number: 8 > 5 > 3 → 853
Smallest number: 3 < 5 < 8 → 358
Example 2
Digits: 7, 0, 4
Greatest number: 7 > 4 > 0 → 740
Smallest number: Can't start with 0! Next smallest is 4. → 407
Example 3 (4 digits)
Digits: 6, 2, 9, 1
Greatest number: 9 > 6 > 2 > 1 → 9,621
Smallest number: 1 < 2 < 6 < 9 → 1,269
Example 4 (4 digits with 0)
Digits: 3, 0, 5, 0
Greatest number: 5 > 3 > 0 > 0 → 5,300
Smallest number: Can't start with 0! Next smallest is 3. → 3,005

Real-Life Comparisons (Indian Context)

Cricket
IPL Match Scores:
Chennai Super Kings scored 185 runs. Mumbai Indians scored 179 runs.
Compare: Hundreds same (1=1), Tens: 8 > 7 → 185 > 179. CSK wins!
Shopping
Comparing Prices:
Rani wants to buy the cheaper notebook. Shop A sells it for ₹45 and Shop B for ₹38.
Compare: Tens: 4 > 3 → 45 > 38. So Shop B is cheaper (₹38 < ₹45).
Geography
Heights of Mountains (in metres):
Nanda Devi: 7,816 m | Kangchenjunga: 8,586 m | K2: 8,611 m
Ascending order: 7,816 < 8,586 < 8,611
(Nanda Devi < Kangchenjunga < K2)

📝 Key Words

WordMeaning
CompareTo find which number is greater, smaller, or equal
Greater than (>)The number on the left is bigger than the number on the right
Less than (<)The number on the left is smaller than the number on the right
Equal to (=)Both numbers have the same value
Ascending orderArranging numbers from smallest to largest
Descending orderArranging numbers from largest to smallest
DigitsThe symbols 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 used to write numbers
Place valueThe value of a digit based on its position (ones, tens, hundreds, thousands)
⭐ Key Points to Remember

Finished learning? Now test what you know!