Multiple choice

In the following number series only one number is wrong. Find out the wrong number. -9, -15, -49, -192, -961, -5759

  1. $-5759$
  2. $-961$
  3. $-192$
  4. $-49$
  5. $-15$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Pattern: each term = previous term × (n+1) - n², where n increases by 1 each time. -9 × 2 - 1² = -19 (not -15). Checking actual: -9, -15 = -9×2+3, -49 = -15×3-4, -192 = -49×4-8, -961 = -192×5-11. The multipliers and subtractions follow patterns but -192 doesn't fit: -49×5-6 = -251 (expected), -49×4-8 = -204 (closer but not exact). Recalculating: -15 = -9×2+3, -49 = -15×3-4, -192 = -49×4-4, -961 = -192×5-11. The pattern breaks at -192.

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