Find the wrong number in the series: 3, 8, 15, 24, 34, 48, 63, …

Difficulty: Easy

Correct Answer: 34

Explanation:


Introduction / Context:
Here the sequence grows by adding consecutive odd numbers to the previous term. Such a pattern is very common: +5, +7, +9, +11, +13, +15, … A single mis-addition creates the odd term out.


Given Data / Assumptions:

  • Series: 3, 8, 15, 24, 34, 48, 63.
  • Intended increments are consecutive odd numbers starting at 5.
  • Only one term deviates from the rule.


Concept / Approach:
Compute successive differences and compare them with the intended odd list. Replace the faulty term with the correctly incremented value to confirm the pattern.


Step-by-Step Solution:
3 + 5 = 8 (OK)8 + 7 = 15 (OK)15 + 9 = 24 (OK)24 + 11 = 35 (but the series shows 34)Continuing intended: 35 + 13 = 48, 48 + 15 = 63


Verification / Alternative check:
With 34 corrected to 35, all steps align perfectly with +5, +7, +9, +11, +13, +15. The later terms 48 and 63 already fit the corrected sequence, proving that 34 is the lone error.


Why Other Options Are Wrong:

  • 15 / 24 / 48: all are consistent with the intended consecutive-odd increments.


Common Pitfalls:

  • Mistaking arbitrary differences; the clean consecutive-odd rule best explains the progression.


Final Answer:
34

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