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Using prime factorisation, √11025 equals:
A{'text': '95'}
B{'text': '115'}
C{'text': '105'}
D{'text': '125'}
Answer & Solution
Correct answer: C. {'text': '105'}
1. Factorise 11025 into primes: 11025 = 3² × 5² × 7² × (1).
2. To take the square root, take one factor from each pair: 3 × 5 × 7 = 105.
3. Hence √11025 = **105**.
4. Verification: 105 × 105 = 11025 ✓.
_Source: Selina Concise ICSE Class 8 Mathematics Ch 3 "Squares and Square Roots", Prime factorisation method_
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