What is the missing number in the series. 6, 15, 35, 77, ?, 221?

3 Answers on this Question

1. 154+11
   165

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2. The terms of the series are products of two consecutive prime numbers i.e. (2 x 3),
   (3 x 5), (5 x 7), (7 x 11),…..
   So, 165 is wrong and must be replaced by (11 x 13) i.e. 143.

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3. 163

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