WEBVTT

1
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Here is the problem: sum of 5 from k equals 1 to 8.

2
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Add the terms 5 for k equals 1, 2, …, 8 (8 terms).

3
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Write the sum.

4
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List the first terms.

5
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Add all 8 terms exactly (as fractions).

6
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So the answer is 40.

7
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Each term is computed exactly and added. For long arithmetic or geometric sums a closed formula gives the same result.

8
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Decimal value: 40.