Number series – Find the wrong number (Fibonacci-style sum of two previous) 2, 5, 7, 12, 19, 32, 50 Exactly one term is incorrect. Identify the wrong number, given the intended rule “each term = sum of previous two terms”.

Introduction / Context:
Many series are built like the Fibonacci sequence: a(n) = a(n−1) + a(n−2). One rogue term will break the recurrence while all others fit perfectly.

Given Data / Assumptions:

• Series: 2, 5, 7, 12, 19, 32, 50
• Target rule: each term equals the sum of its two immediate predecessors.

Concept / Approach:
Verify the sum-of-previous-two rule at every step and find the single violation.

Step-by-Step Solution:
2 + 5 = 7 → OK.5 + 7 = 12 → OK.7 + 12 = 19 → OK.12 + 19 = 31 → should be 31, but the series shows 32 → violation.19 + 31 = 50 → the last term 50 is consistent if “32” is corrected to 31.

Verification / Alternative check:
Replacing 32 with 31 restores the recurrence across the whole tail, proving 32 is the lone error.

Why Other Options Are Wrong:

• 7, 12, 19 → all satisfy the rule with the corrected middle term.
• None of these → incorrect; 32 is uniquely inconsistent.

Common Pitfalls:
Mistaking the last number (50) as wrong because it is large; it actually validates once the prior term is fixed.

Final Answer:
32