Difficulty: Easy
Correct Answer: 492
Explanation:
Introduction / Context:
This is a number analogy question where one three digit number is connected to another by a simple arithmetic pattern. Once you identify the rule that converts 534 to 645, you must apply that same rule to 381 to obtain the missing related number.
Given Data / Assumptions:
Concept / Approach:
For numeric analogies, it is natural to first check the difference between the numbers in the first pair. If the difference is simple and clean, that difference is often the rule to use for the second pair. Occasionally, operations on individual digits are involved, but here a direct difference works very well and keeps the question at an easy level.
Step-by-Step Solution:
Verification / Alternative check:
We can quickly test whether any of the other options give a constant difference when compared with 381. For example, 446 − 381 = 65, 486 − 381 = 105, and 412 − 381 = 31. None of these match 111. Only 492 − 381 = 111 which is exactly the difference found in the first pair, hence confirming the rule.
Why Other Options Are Wrong:
Common Pitfalls:
Some candidates overcomplicate such questions by trying to manipulate individual digits or by searching for squares or cubes. Others may spot an incorrect difference due to arithmetic mistakes and then carry that error into the second pair. Careful subtraction and choosing the simplest possible pattern usually leads to the correct answer efficiently.
Final Answer:
Using the same rule, 381 is related to 492.
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