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Class 9MathematicsSequences and ProgressionsSum of first n natural numbersEasyLevel 63
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If the sum of the first (n) natural numbers is (861), what is the value of (n)?

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Answer and explanation

Correct answer: (41)

(S_{41}=\frac{41\times42}{2}=861), so (n=41). In such questions, check the options in the formula.

Related tags

MathSequencesNatural-NumbersSum

Frequently asked questions

What is the correct answer to this question?

(41)

Why is this the correct answer?

(S_{41}=\frac{41\times42}{2}=861), so (n=41). In such questions, check the options in the formula.

Which subject and chapter does this question cover?

This is a Class 9 Mathematics question. Chapter: Sequences and Progressions. Topic: Sum of first n natural numbers.

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