What is a 4-Digit Number?

S1-SA1-0001

Grade Level:

Class 3

Maths, Computing, Finance, Data Science

Definition

What is it?

A 4-digit number is any whole number that has exactly four digits. These digits are arranged in specific places: thousands, hundreds, tens, and ones. The smallest 4-digit number is 1000 and the largest is 9999.

Simple Example

Quick Example

Imagine you are checking the price of a new smartphone. If it costs ₹12,500, this is a 5-digit number. But if it costs ₹9,999, this is a 4-digit number because it has exactly four digits: 9, 9, 9, and 9.

Worked Example

Step-by-Step

Let's find out if the number 3,456 is a 4-digit number.
---Step 1: Count the number of digits in 3,456.
---Step 2: The digits are 3, 4, 5, and 6.
---Step 3: There are four digits in total.
---Step 4: Since it has exactly four digits, 3,456 is a 4-digit number.
Answer: Yes, 3,456 is a 4-digit number.

Why It Matters

Understanding 4-digit numbers is crucial for handling money, reading large data sets, and even understanding phone numbers. In finance, you'll use them for budgets, and in data science, to count items. Many jobs, from banking to coding, rely on knowing how to work with numbers of all sizes.

Common Mistakes

MISTAKE: Thinking 0999 is a 4-digit number | CORRECTION: 0999 is actually a 3-digit number (999) because the leading zero doesn't count as a digit for number value. A 4-digit number must start with a digit from 1 to 9.

MISTAKE: Confusing 1,000 with 100 | CORRECTION: 1,000 has four digits (1, 0, 0, 0) and is a 4-digit number. 100 has three digits (1, 0, 0) and is a 3-digit number.

MISTAKE: Forgetting place value, e.g., thinking 1234 is the same as 4321 | CORRECTION: The position of each digit matters. In 1234, the '1' is in the thousands place. In 4321, the '4' is in the thousands place, making them very different numbers.

Practice Questions

Try It Yourself

QUESTION: Is 789 a 4-digit number or a 3-digit number? | ANSWER: 3-digit number

QUESTION: What is the smallest 4-digit number? | ANSWER: 1000

QUESTION: Write down a 4-digit number where the hundreds digit is 5, the tens digit is 2, the ones digit is 8, and the thousands digit is 6. | ANSWER: 6528

MCQ

Quick Quiz

Which of these is NOT a 4-digit number?

1001

9999

8765

999

The Correct Answer Is:

Option D, 999, has only three digits (9, 9, 9), so it is a 3-digit number. Options A, B, and C all have exactly four digits.

Real World Connection

In the Real World

When you check your bank balance or see the price of a new scooter, you often encounter 4-digit numbers. For instance, the price of a ticket for a train journey from Delhi to Mumbai might be ₹1,500, which is a 4-digit number. Even the number of runs scored by a batsman in a cricket series could be a 4-digit number like 1,250 runs.

Key Vocabulary

Key Terms

Digit: A single symbol used to write numbers (0, 1, 2, 3, 4, 5, 6, 7, 8, 9) | Place Value: The value of a digit based on its position in a number | Thousands Place: The position of the fourth digit from the right in a number | Whole Number: A number without fractions or decimals

What's Next

What to Learn Next

Now that you understand 4-digit numbers, you can explore larger numbers like 5-digit or 6-digit numbers. You'll also learn about how to compare and order these numbers, which is essential for understanding more complex math concepts.