Multiple choice

Find out the wrong number in the series. 445,221,109,46,25,11

  1. 221

  2. 109

  3. 46

  4. 25
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C Correct answer
Explanation

The pattern is: divide by 2 and subtract consecutive odd numbers (1, 3, 5, 7, 9). Starting with 445: 445÷2-1=221, 221÷2-3=109, 109÷2-5=49 (not 46), 49÷2-7=18, 18÷2-9=0. The number 46 breaks this pattern - it should be 49.

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