📚 Class 2 Mathematics – Chapter 2: Addition
🔹 1. Introduction
Addition is the process of joining two or more numbers to get a total.
The symbol for addition is “+”.
The result of addition is called the sum.
💡 Example:
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5 + 3 = 8
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Here, 5 and 3 are addends, and 8 is the sum.
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🔹 2. Addition of Small Numbers (Within 20)
Start with small numbers, then gradually move to larger numbers.
Example:
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7 + 5 = ?
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Count 7 first → 8, 9, 10, 11, 12
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Answer = 12
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🔹 3. Addition Using Number Line
A number line helps in visualizing addition.
Example: 6 + 4 = ?
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Start at 6 on the number line.
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Move 4 steps forward → 7, 8, 9, 10
✅ Answer: 10
🔹 4. Addition of Tens and Ones (Two-digit Numbers)
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Add ones first, then tens.
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If ones > 9, carry over to tens.
Example: 23 + 17
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Add ones: 3 + 7 = 10 → write 0, carry 1
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Add tens: 2 + 1 + 1 (carry) = 4
✅ Answer: 40
🔹 5. Addition with Carry Over
Step 1: Add ones
Step 2: Write the unit digit, carry the tens
Step 3: Add tens along with carry
Example: 48 + 36
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Ones: 8 + 6 = 14 → write 4, carry 1
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Tens: 4 + 3 + 1 = 8
✅ Answer: 84
🔹 6. Addition of Three Numbers
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Add first two numbers, then add the third.
Example: 5 + 7 + 3
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Step 1: 5 + 7 = 12
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Step 2: 12 + 3 = 15
✅ Answer: 15
💡 Tip: You can also rearrange numbers to make addition easier (Commutative Property).
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3 + 5 + 7 = 15
🔹 7. Properties of Addition
7.1 Commutative Property
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Changing the order of numbers does not change the sum.
Example: 5 + 7 = 7 + 5 = 12
7.2 Associative Property
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Grouping numbers differently does not change the sum.
Example: (5 + 3) + 2 = 5 + (3 + 2) = 10
7.3 Zero Property
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Adding 0 to any number does not change the number.
Example: 7 + 0 = 7
🔹 8. Word Problems (Simple Addition)
1️⃣ Ram has 7 apples. His friend gives him 5 more. How many apples does Ram have?
✅ Answer: 7 + 5 = 12 apples
2️⃣ There are 12 birds on a tree. 8 more birds come. How many birds are there now?
✅ Answer: 12 + 8 = 20 birds
🔹 9. Practice Questions
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15 + 6 = ?
✅ Answer: 21 -
24 + 17 = ?
✅ Answer: 41 -
8 + 9 + 3 = ?
✅ Answer: 20 -
Add 48 + 27 using carry over method.
✅ Answer: 75 -
Solve: A shop has 23 pencils. 17 more pencils arrive. How many pencils in total?
✅ Answer: 23 + 17 = 40
🔹 10. Summary
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Addition = joining numbers to get a sum
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Symbols: + → “plus”
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Properties: Commutative, Associative, Zero Property
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Methods: Using number line, carry over method, and adding three or more numbers
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Word Problems: Apply addition in real-life situations