What is Forty-Five (45)? | Simple Explanation for Class 5-10

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What is Forty-Five?

Grade Level:

Pre-School – Class 2

All domains without exception

Definition

What is it?

Forty-five is a number that comes after forty-four and before forty-six. It represents a quantity of 4 tens and 5 ones, written as '45'.

Simple Example

Quick Example

Imagine you have 4 bundles of 10 laddoos each, and then 5 more loose laddoos. If you count all of them together, you will have a total of forty-five laddoos. That's how much '45' means!

Worked Example

Step-by-Step

Let's find out how many items make up 'forty-five'.
1. Start with 10 items (like 10 pencils).
2. Add another 10 items. Now you have 20 pencils.
3. Add another 10 items. Now you have 30 pencils.
4. Add another 10 items. Now you have 40 pencils.
5. Now, add 5 more items. 40 + 5 = 45 pencils.
--- So, forty-five is the total number of pencils.

Why It Matters

Understanding numbers like forty-five is fundamental for all math concepts, from basic counting to complex calculations. It's used by everyone from shopkeepers calculating change to engineers designing buildings, and even by cricket statisticians tracking scores.

Common Mistakes

MISTAKE: Writing '405' when someone says 'forty-five' | CORRECTION: 'Forty-five' means 4 tens and 5 ones, which is written as '45'. '405' means four hundred and five.

MISTAKE: Confusing 'forty-five' (45) with 'fifty-four' (54) | CORRECTION: Pay attention to the order of the digits. 'Forty-five' has the '4' (four tens) first, then '5' (five ones). 'Fifty-four' has '5' (five tens) first, then '4' (four ones).

MISTAKE: Thinking 'forty-five' is just 'four' and 'five' | CORRECTION: It's not just 4 and 5 next to each other. It means 4 groups of ten and 5 individual units, showing the importance of place value.

Practice Questions

Try It Yourself

QUESTION: If you have 20 rupees and your friend gives you 25 more rupees, how many rupees do you have in total? | ANSWER: 45 rupees

QUESTION: A bus has 45 seats. If 20 passengers are already seated, how many more passengers can sit? | ANSWER: 25 passengers

QUESTION: Rahul scored 15 runs in the first cricket match, 10 runs in the second, and then 20 runs in the third match. What is his total score across all three matches? | ANSWER: 45 runs

MCQ

Quick Quiz

Which of these represents 'forty-five'?

405

504

The Correct Answer Is:

Forty-five is written as 45, where '4' is in the tens place and '5' is in the ones place. Options A, B, and D represent different numbers.

Real World Connection

In the Real World

You see forty-five everywhere! For example, when you check your phone's battery percentage, it might be 45%. Or when you buy something for ₹45 from a street vendor, you are using this number. Even the number of minutes in a typical school period can sometimes be 45 minutes.

Key Vocabulary

Key Terms

NUMBER: A mathematical object used for counting, measuring, and labeling | 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 | TENS PLACE: The second position from the right in a whole number, representing groups of ten

What's Next

What to Learn Next

Now that you understand what forty-five is, you're ready to explore larger numbers and learn about counting in hundreds and thousands. Keep practicing, and you'll become a number expert!