Class 8 Maths – Chapter 16: Playing with Numbers
Step 3: Divisibility Rules (4, 6, 8, 11)
1️⃣ Divisibility Rule of 4
A number is divisible by 4 if the number formed by its last two digits is divisible by 4.
Example: 1316 → last two digits = 16 ✔
2️⃣ Divisibility Rule of 6
A number is divisible by 6 if it is divisible by both 2 and 3.
Example: 234 ✔ (even and digit sum = 9)
3️⃣ Divisibility Rule of 8
A number is divisible by 8 if the number formed by its last three digits is divisible by 8.
Example: 7456 → last three digits = 456 ✔
4️⃣ Divisibility Rule of 11
A number is divisible by 11 if the difference between the sum of digits in odd places and even places is 0 or a multiple of 11.
Example: 121 → (1+1) − 2 = 0 ✔
📌 Worked Examples
- 132 → Divisible by 6 ✔
- 3128 → Divisible by 8 ✔
- 462 → Divisible by 11 ✘
📘 Exam Writing Tips
- Mention rule name clearly
- Show calculation steps
- Conclude with “Hence divisible / not divisible”
🧠Easy Memory Trick:
4 → Last 2 digits | 6 → (2 & 3) | 8 → Last 3 digits | 11 → Odd–Even difference
📘 Class 8 Mathematics – Complete Library
CBSE | NCERT | State Syllabus
Chapter 1: Rational Numbers
Chapter 2: Linear Equations in One Variable
Chapter 3: Understanding Quadrilaterals
Chapter 4: Practical Geometry
Chapter 5: Data Handling
Chapter 6: Squares and Square Roots
Chapter 7: Cubes and Cube Roots
- NCERT Notes
- MCQs
- Worksheet
- Worksheet Answers
- Mind Map & Easy Tricks
- Important Exam Questions
- Very Important Questions
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