Multiple choice

Directions: Find the missing term of the series given below. 6, 15, 35, 77, ?, 221, 323

  1. 143

  2. 153

  3. 163

  4. 173

  5. None of these
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A Correct answer
Explanation

The series is 2*3, 3*5, 5*7, 7*11, 11*13, 13*17, 17*19. The missing term is 11*13 = 143.

AI explanation

The series follows a pattern of multiplying consecutive prime numbers together and then multiplying by an increasing integer. The terms correspond to 3 times 2, 5 times 3, 7 times 5, 11 times 7, 13 times 11, 17 times 13, and 19 times 17. Multiplying 13 by 11 gives the missing term of 143.

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