Multiple choice

Find the wrong number in the following number series 32, 39, 65, 128, 253, 467, 809, 1320

  1. 39

  2. 65

  3. 253

  4. 467

  5. 32
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The series follows the pattern: each term is double the previous term minus consecutive odd numbers (7, 9, 11, 13, 15, 17, 19). Checking: 39×2-13=65, 65×2-15=115, 128×2-17=239. Since 253 should be 239, it breaks the pattern. Alternatively, check that all other terms fit: 128×2-17=239 (not 253), 253×2-19=487 (not 467), 467×2-23=911 (not 809). The position of 253 is clearly wrong.

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