What is Thirty?

S0-SA1-0584

Grade Level:

Pre-School – Class 2

All domains without exception

Definition

What is it?

Thirty is the natural number that comes after twenty-nine and before thirty-one. It is written as '30' in digits and 'thirty' in words. Thirty is a two-digit number where the digit '3' is in the tens place and '0' is in the ones place.

Simple Example

Quick Example

Imagine you have collected 10 rupees, then your friend gives you another 10 rupees, and then your mom gives you 10 more rupees. If you add all this money together, you will have 30 rupees in total. That's thirty!

Worked Example

Step-by-Step

Let's count to thirty using a simple addition.
Step 1: Start with 25.
---Step 2: Add 1 to 25. You get 26.
---Step 3: Add 1 more to 26. You get 27.
---Step 4: Add 1 more to 27. You get 28.
---Step 5: Add 1 more to 28. You get 29.
---Step 6: Add 1 more to 29. You get 30.
Answer: So, 25 + 1 + 1 + 1 + 1 + 1 = 30.

Why It Matters

Understanding numbers like thirty is the very first step in all of mathematics and science. It helps you count, measure, and solve problems in daily life. From being a shopkeeper calculating change to an engineer designing bridges, numbers are fundamental to almost every career.

Common Mistakes

MISTAKE: Confusing thirty (30) with three (3) or thirteen (13). | CORRECTION: Remember that 'thirty' has a 't' sound at the end like 'twenty' and 'forty', and it's a two-digit number starting with 3.

MISTAKE: Writing '03' instead of '30' for thirty. | CORRECTION: The '3' must be in the tens place and '0' in the ones place for thirty. '03' is just another way to write three.

MISTAKE: Thinking thirty is less than twenty-five. | CORRECTION: Always remember the number line; numbers increase as you move to the right. Thirty comes after twenty-five, so it is greater.

Practice Questions

Try It Yourself

QUESTION: How many tens are there in thirty? | ANSWER: 3 tens

QUESTION: If you have 20 mangoes and buy 10 more, how many mangoes do you have in total? | ANSWER: 30 mangoes

QUESTION: A cricket team scored 15 runs in the first 5 overs and then 15 more runs in the next 5 overs. What is their total score? | ANSWER: 30 runs

MCQ

Quick Quiz

Which of these numbers is thirty?

300

The Correct Answer Is:

Option C, '30', correctly represents thirty. Options A, B, and D represent three, thirteen, and three hundred, respectively, which are different numbers.

Real World Connection

In the Real World

In India, you might see '30' on a bus route number, or a shopkeeper might tell you the price of a packet of biscuits is 'thirty rupees'. Many school holidays might last for 30 days. Even your mobile data plan might give you 30 GB per month!

Key Vocabulary

Key Terms

NUMBER: A count or measurement | DIGIT: A single symbol used to write numbers (0, 1, 2, ... 9) | TENS PLACE: The second digit from the right in a number, representing groups of ten | ONES PLACE: The first digit from the right in a number, representing single units

What's Next

What to Learn Next

Great job understanding thirty! Next, you should learn about 'What is Forty?'. This will help you understand how numbers continue to grow in groups of ten and build a strong foundation for larger numbers.