What is 4 + 5?

S1-SA1-0647

Grade Level:

Class 1

Maths, Computing, AI

Definition

What is it?

4 + 5 is an addition problem asking you to combine the quantity of 4 with the quantity of 5. It helps us find the total number when these two amounts are put together.

Simple Example

Quick Example

Imagine you have 4 ladoos on one plate and your friend gives you 5 more ladoos. How many ladoos do you have in total? This is exactly what 4 + 5 helps you figure out.

Worked Example

Step-by-Step

Let's find the sum of 4 + 5.

STEP 1: Start with the first number, which is 4.
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STEP 2: Now, count forward 5 times from 4. You can use your fingers or draw dots.
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STEP 3: Start at 4. Count 1 more: 5.
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STEP 4: Count 2 more: 6.
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STEP 5: Count 3 more: 7.
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STEP 6: Count 4 more: 8.
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STEP 7: Count 5 more: 9.
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So, 4 + 5 = 9.

Why It Matters

Understanding addition is fundamental to all of Maths, Computing, and even AI! It's used by software developers to calculate game scores, by data scientists to sum up sales figures, and by AI engineers to process information in complex algorithms. It's the building block for so many cool careers!

Common Mistakes

MISTAKE: Counting the starting number again (e.g., counting 4, then 1, 2, 3, 4, 5 for 4+5, getting 8) | CORRECTION: Start counting from the number AFTER the first number. So, for 4+5, you start counting from 5, then 6, 7, 8, 9 (which is 5 counts).

MISTAKE: Mixing up addition with subtraction (e.g., thinking 4 + 5 means taking away) | CORRECTION: Remember 'plus' (+) means 'put together' or 'find the total'. 'Minus' (-) means 'take away' or 'find the difference'.

MISTAKE: Not lining up numbers correctly in bigger addition problems (though not relevant for 4+5, it's a general addition mistake) | CORRECTION: Always align numbers by their place value (ones under ones, tens under tens) when adding larger numbers vertically.

Practice Questions

Try It Yourself

QUESTION: You have 3 red pencils and 6 blue pencils. How many pencils do you have in total? | ANSWER: 9 pencils (3 + 6 = 9)

QUESTION: Your mobile phone has 7GB of data left. You recharge with 2GB more. How much data do you have now? | ANSWER: 9GB (7 + 2 = 9)

QUESTION: A small auto-rickshaw ride costs ₹4. If you take two such rides, and then another ride costs ₹5, what is the total cost for all three rides? | ANSWER: ₹13 (4 + 4 + 5 = 13)

MCQ

Quick Quiz

What is the sum of 4 and 5?

The Correct Answer Is:

When you combine 4 and 5, you get a total of 9. Options A, B, and D are incorrect as they do not represent the correct sum of 4 and 5.

Real World Connection

In the Real World

When you use UPI to pay for chai at a stall, the app adds up the cost of your chai and maybe a biscuit to give you the total. Or, when a cricket team's score is updated, the new runs are added to the previous score, just like 4 + 5, to show the current total.

Key Vocabulary

Key Terms

ADDITION: The process of combining two or more numbers to find their total | SUM: The result obtained when numbers are added together | PLUS SIGN (+): The symbol used to indicate addition | TOTAL: The whole amount or number of something

What's Next

What to Learn Next

Great job understanding 4 + 5! Next, you should learn about 'Addition with Larger Numbers' and 'Addition with Carrying'. These concepts build on what you've learned here and will help you solve even bigger and more complex addition problems!