\"\"

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The given expression is \"\".

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Method 1

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Find the terms by replacing n with 1, 2, 3, 4, and 5.

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Substitute n values in \"\".\"\"\"\"

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\"\"

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\"\"

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\"\"

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The sum of an arithmetic series \"\".

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Where \"\" is the first term and \"\" is the nth term.

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Method 2

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There are 5 terms, \"\" and \"\".

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The fifth term of the arithmetic sequence \"\"

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\"\"                        (Substitute \"\")

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\"\"                              (Subtract: \"\")

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\"\"                                    (Multiply: \"\")

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\"\"                                      (Divide: \"\")\"\"

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The sum of the arithmetic series is \"\".