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The smallest natural number by which 50 must be multiplied to make it a perfect square is:
A{'text': '2'}
B{'text': '3'}
C{'text': '5'}
D{'text': '6'}
Answer & Solution
Correct answer: A. {'text': '2'}
1. Factorise 50 = 2 × 5 × 5 = 2 × 5².
2. The prime factor 2 appears only once — it lacks a pair.
3. Multiplying by 2 gives 100 = 2² × 5², a perfect square (10²).
4. So the required smallest multiplier is **2**.
_Source: Selina Concise ICSE Class 8 Mathematics Ch 3 "Squares and Square Roots", Prime factorisation method_
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