Part of CBSE Class 8 Mathematics on Lipi
About this chapter
The Proof Hiding in Every Digit Sum · CBSE Class 8 Mathematics. Why the 9-Digit Trick Works: A number is divisible by 9 exactly when its digit sum is divisible by 9, because every power of 10 is 1 more than a multiple of 9.
The Proof Hiding in Every Digit Sum
Number Play
Covers Summary, Central idea, Key facts, Word meanings, and more.
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What this chapter covers
- Summary
- Central idea
- Key facts
- Word meanings
- Themes
- Common mistakes
- Remember this
- Required practical
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The full lesson opens all 11 sections: summaries, word meanings and model answers, in the language of the book.
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