Multiple choice

Find the wrong number in the following number series -44 -27 9 39 92 161

  1. 39

  2. 9

  3. -44

  4. 161

  5. -27
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The series follows the pattern n³ - 2n² - 5n - 38, where n is the position. Checking: n=1: 1-2-5-38=-44 ✓; n=2: 8-8-10-38=-48 (not -27); n=3: 27-18-15-38=-44 (not 9); n=4: 64-32-20-38=-26 (not 39); n=5: 125-50-25-38=12 (not 92). This pattern doesn't fit. The actual pattern is the differences of differences: 17, 36, 30, 53, 69 have second differences of 19, -6, 23, 16. The number 9 doesn't fit the alternating pattern seen in the other terms.

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