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Per NCERT, what is the sum of the first 20 natural numbers (1 + 2 + ... + 20)?
A420
B200
C210 (= 20 × 21 / 2)
D220
Answer & Solution
Correct answer: C. 210 (= 20 × 21 / 2)
Per NCERT, S₂₀ = 20 × 21 / 2 = 210.
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