Multiple choice

Find the wrong term in the given series. 15, 30, 54, 88, 129, 180

  1. 88

  2. 30

  3. 129

  4. 180

  5. 54
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A Correct answer
Explanation

Find the pattern in differences: 30-15=15, 54-30=24, 88-54=34, 129-88=41, 180-129=51. Differences: 15, 24, 34, 41, 51. Second differences: 9, 10, 7, 10. This is irregular. Try another approach: 15+15=30, 30+24=54, 54+34=88 (should be 54+36=90 for +6 pattern). Check 88 in context: if the pattern should give +36 (difference of differences +6), then position 4 should be 90, not 88. So 88 is wrong.

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