Multiple choice

The odd term out in the series 15, 16, 34, 105, 424, 2124, 12756 is

  1. 105

  2. 16

  3. 2124

  4. 34
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C Correct answer
Explanation

The pattern is: 15*1+1=16, 16*2+2=34, 34*3+3=105, 105*4+4=424, 424*5+5=2125. The term 2124 is incorrect; it should be 2125.

AI explanation

The pattern uses the logic of multiplying by increasing integers and then adding or subtracting a constant to get the next term. The sequence progresses as (15 x 1) + 1 = 16, (16 x 2) + 2 = 34, (34 x 3) + 3 = 105, and (105 x 4) + 4 = 424. The next term should be (424 x 5) + 5 = 2125, making 2124 the odd term out.

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