Difficulty: Medium
Correct Answer: 6
Explanation:
Introduction / Context:
Certain number analogies rely on properties of digits rather than arithmetic alone. One popular device is to map a two-digit display AB to a value derived from the digits’ properties. The pair “08 : 66” hints at a function that also works if a leading zero is present (like 06).
Given Data / Assumptions:
Concept / Approach:
A workable pattern is f(a, b) = a^2 + b^2 + 2. This yields f(0, 8) = 0^2 + 8^2 + 2 = 64 + 2 = 66. Using the same rule to reach 38, we need a^2 + b^2 = 36; the neat two-digit candidate is (0, 6), i.e., “06,” which is often written as “6.”
Step-by-Step Solution:
1) From 08 → 66 infer f(a, b) = a^2 + b^2 + 2.2) Solve a^2 + b^2 + 2 = 38 ⇒ a^2 + b^2 = 36.3) Choose (0, 6) giving 0 + 36 = 36 → 38; hence “06,” which corresponds to option “6.”
Verification / Alternative check:
Other listed options do not admit any two-digit split with sum of squares 36 under this exact rule; 12 gives 1 + 4 + 2 = 7; 19 gives 1 + 81 + 2 = 84, etc.
Why Other Options Are Wrong:
Common Pitfalls:
Missing the allowance for a leading zero; the exemplar “08” makes that explicit.
Final Answer:
6
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