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प्रश्न
Select the correct alternative and write it.
What is the sum of first n natural numbers ?
पर्याय
(A)` (n(n-1))/2`
(B)`n/2(n-2)`
(c)` n(n+1)/2`
(D) `(n(n+2))/2`
उत्तर
(c) `(n(n+1))/2`
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