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Which of these numbers is a perfect square?
A{'text': '1024'}
B{'text': '1023'}
C{'text': '1025'}
D{'text': '1026'}
Answer & Solution
Correct answer: A. {'text': '1024'}
1. A perfect square is the square of some natural number.
2. Try 32: 32 × 32 = 1024.
3. So 1024 = 32² is a perfect square.
4. The other three differ from 1024 by ±1 or ±2 and lie between 32² and 33² (= 1089), so they cannot be perfect squares.
5. Hence the answer is **1024**.
_Source: Selina Concise ICSE Class 8 Mathematics Ch 3 "Squares and Square Roots", Properties of square numbers_
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