√396900 equals:
A{'text': '630'}
B{'text': '520'}
C{'text': '580'}
D{'text': '680'}
Answer & Solution
Correct answer: A. {'text': '630'}
1. Prime factorise 396900 = 2² × 3² × 5² × 3² × 7² × 1.
2. Group as squares: 396900 = (2·3·5·3·7)² = (630)².
3. So √396900 = 630.
4. Verification: 630² = 396900 ✓.
5. Hence the answer is **630**.
_Source: Selina Concise ICSE Class 8 Mathematics Ch 3 "Squares and Square Roots", Prime factorisation worked examples_
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