Multiple choice

Directions: Find the missing term in the following number series. 2, 15, 54, 171, 522, ?

  1. 2075

  2. 1575

  3. 1914

  4. 1585

  5. None of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Series: 2, 15, 54, 171, 522. Differences: 13, 39, 117, 351. These are powers of 3 times 13: 13*1, 13*3, 13*9, 13*27. Next difference = 13 * 81 = 1053. 522 + 1053 = 1575.

AI explanation

The series follows a pattern where each term is multiplied by three and then a sequential odd number is subtracted. Multiplying 2 by 3 gives 6, and subtracting 3 gives 3 (not 15); however, using the correct logic of multiplying by 3 and adding successive powers of 3 gives the sequence: 2(3) + 3^2 = 15, 15(3) + 3^3 = 54, 54(3) + 3^4 = 171, and 171(3) + 3^5 = 522. Continuing this established pattern, the next term is 522(3) + 3^6, which equals 1566 + 729 = 1575.

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