\"\"

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The series is \"\" if \"\".

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Find the missing property sequence.

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The common ratio is \"\"

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The general formula of  \"\"-term sum of a geometric series \"\".

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Find \"\".

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Substitute \"\", \"\" and \"\".

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\"\"

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\"\"

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The value of  \"\" is \"\".

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\"\"

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The value of  \"\" is \"\".