Difficulty: Easy
Correct Answer: 312
Explanation:
Introduction / Context:A fixed subtraction pattern, especially by a notable square like 121 (=11^2), is common in reasoning sets. Confirm the fixed drop and extend once more.
Given Data / Assumptions:
Concept / Approach:Apply the same subtraction again.
Step-by-Step Solution:
433 − 121 = 312.Verification / Alternative check:Adding back 121 from 312 returns to 433, confirming consistency.
Why Other Options Are Wrong:
231, 213, 512 do not equal 433 − 121 and would break the uniform decrement.Common Pitfalls:Searching for changing differences where a single constant drop fits perfectly.
Final Answer:312
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