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The sum of the first 5 odd natural numbers (1 + 3 + 5 + 7 + 9) equals:
A{'text': '20'}
B{'text': '30'}
C{'text': '25'}
D{'text': '35'}
Answer & Solution
Correct answer: C. {'text': '25'}
1. A useful identity: sum of first n odd natural numbers = n².
2. Here n = 5, so the sum equals 5² = 25.
3. Direct check: 1 + 3 + 5 + 7 + 9 = 25 ✓.
4. Hence the answer is **25**.
_Source: Selina Concise ICSE Class 8 Mathematics Ch 3 "Squares and Square Roots", Sum of odd numbers property_
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