Multiple choice

In each of the following series only one number is wrong. You have to find out that wrong number. 15 32 66 141 298 621

  1. 15

  2. 66

  3. 141

  4. 298

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

Testing the pattern: Each term ×2+2 should give next term (×1.5, ×2.5 alternating or mixed). Pattern varies but 15, 32, 66, 141, 298, 621 suggests no single term is definitively 'wrong'. The pattern could be ×2+2, ×2.5+1, ×2+9, etc. No clear single wrong number. E (None of these) is appropriate as the series is ambiguous.

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