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The sum of 20 terms of a series of whi...

The sum of 20 terms of a series of which every even term is 2 times the term before it, every odd term is 3 times the term before it, the first term being unity is a. `(2/7)(6^(10)-1)` b. `(3/7)(6^(10)-1)` c.`(3/5)(6^(10)-1)` d. none of these

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CENGAGE PUBLICATION-SEQUENCES AND SERIES-All Questions
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  3. The sum of 20 terms of a series of which every even term is 2 times ...

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