Multiple choice

Each of the following number series one number is wrong. Find out the odd number. (4 \quad 9 \quad 26 \quad 84 \quad 342 \quad 1716 \quad 10302)

  1. 1716

  2. 84

  3. 9

  4. 26

  5. 10302
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Pattern: 4×1+5=9, 9×2+8=26, 26×3+6=84, 84×4+6=342, 342×5+6=1716... But checking carefully: 4×1=4, 4+5=9; 9×2=18, 18+8=26; 26×3=78, 78+6=84; 84×4=336, 336+6=342; 342×5=1710, 1710+6=1716; 1716×6=10296, 10296+6=10302. Wait, 9 is wrong! The first term should be 4, not 9. Actually, rechecking: 4 to 9 (+5), 9 to 26 (×2+8), 26 to 84 (×3+6)... pattern breaks at start. 9 doesn't fit a clear pattern with 4.

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