WEBVTT

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Here is the problem: Σ k for k equals 1 to 10.

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Add the terms k for k equals 1, 2, …, 10 (10 terms).

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Write the sum.

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List the first terms.

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Add all 10 terms exactly (as fractions).

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So the answer is 55.

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Each term is computed exactly and added. For long arithmetic or geometric sums a closed formula gives the same result.

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Decimal value: 55.