Multiple choice

Which one number is wrong in the given series? 76 80 89 117 163 284

  1. 89

  2. 163

  3. 117

  4. 80
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The differences are: 80-76=4, 89-80=9, 117-89=28, 163-117=46, 284-163=121. Looking at the differences: 4, 9, 28, 46, 121. The difference of differences: 9-4=5, 28-9=19, 46-28=18, 121-46=75. The pattern breaks at 117. If 117 were correct, the sequence would follow a smoother pattern.

Keep practicing — related questions