What is Eighty-Four (84)? | Simple Explanation for Class 5-10

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What is Eighty-Four?

Grade Level:

Pre-School – Class 2

All domains without exception

Definition

What is it?

Eighty-Four is a natural number that comes after eighty-three and before eighty-five. It is written as 84 in numerals. It represents a quantity of eighty groups of ten and four more.

Simple Example

Quick Example

Imagine you have 84 laddoos in a box. This means you have a total of eighty-four sweet laddoos. If you eat one, you'll have eighty-three left, and if you add one more, you'll have eighty-five.

Worked Example

Step-by-Step

Let's say your dad gives you Rs. 84 for your pocket money for the week. How can you count this amount?

1. Start with Rs. 10 notes. Count eight Rs. 10 notes. This gives you 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 = Rs. 80.
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2. Now you need Rs. 4 more. Count four Rs. 1 coins. This gives you 1 + 1 + 1 + 1 = Rs. 4.
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3. Add the two amounts together: Rs. 80 (from the Rs. 10 notes) + Rs. 4 (from the Rs. 1 coins).
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4. Rs. 80 + Rs. 4 = Rs. 84.

So, Rs. 84 is made up of eight tens and four ones.

Why It Matters

Understanding numbers like eighty-four is fundamental for everyday life, from managing your pocket money to understanding cricket scores. It's crucial for subjects like Mathematics, Physics, and even Computer Science. Accountants, shopkeepers, and even scientists use numbers constantly.

Common Mistakes

MISTAKE: Writing 'eighty-four' as '804' | CORRECTION: Remember that 'eighty' means 8 tens, and 'four' means 4 ones. So, it's 8 followed by 4, which is 84.

MISTAKE: Confusing 'eighty-four' with 'forty-eight' | CORRECTION: 'Eighty-four' has 8 in the tens place and 4 in the ones place (84). 'Forty-eight' has 4 in the tens place and 8 in the ones place (48). The order of digits matters a lot!

MISTAKE: Thinking 84 is a small number when dealing with hundreds or thousands | CORRECTION: While 84 is smaller than 100 or 1000, it's still a significant quantity. Always consider the context; 84 marks out of 100 is excellent, but 84 paise might not buy much.

Practice Questions

Try It Yourself

QUESTION: What number comes just after eighty-three? | ANSWER: Eighty-four (84)

QUESTION: If you have 8 bundles of 10 pencils each, and 4 loose pencils, how many pencils do you have in total? | ANSWER: 84 pencils

QUESTION: Your mom bought 8 dozen bananas. How many bananas did she buy? (Hint: 1 dozen = 12) | ANSWER: 96 bananas (8 x 12 = 96). This is a trick question to ensure you understand that 84 is not always the answer!

MCQ

Quick Quiz

Which of these represents the number eighty-four?

804

8 + 4

The Correct Answer Is:

Option C, 84, is the correct numeral for eighty-four. Option A is forty-eight, Option B is eight hundred four, and Option D is the sum of 8 and 4, which is 12.

Real World Connection

In the Real World

When you see a cricket score like 'India needs 84 runs to win', you immediately know the target. Or, if a train journey takes 84 minutes, you can quickly estimate it's about an hour and twenty-four minutes. Even calculating your mobile data usage, say 84 GB used, requires understanding this number.

Key Vocabulary

Key Terms

NUMBER: A count or measure | DIGIT: A single symbol used to write numbers (0-9) | PLACE VALUE: The value of a digit based on its position in a number (ones, tens, hundreds) | NUMERAL: A symbol or name that represents a number

What's Next

What to Learn Next

Now that you understand individual numbers like eighty-four, you're ready to explore how numbers combine in addition and subtraction. This will help you solve more complex problems, like calculating total scores or remaining quantities.