Difficulty: Easy
Correct Answer: 12
Explanation:
Introduction / Context:This is a rule-finding puzzle. An unusual operator “*” is defined implicitly by examples. We must infer the hidden rule from two instances and apply it to a third.
Given Data / Assumptions:
Concept / Approach:Try simple digit operations combined with the second operand: dividing the first number by the second and summing the digits of the quotient fits both given examples.
Step-by-Step Solution:
Test rule on 264 * 2: 264 ÷ 2 = 132; digit sum = 1 + 3 + 2 = 6 ✔. Test rule on 870 * 3: 870 ÷ 3 = 290; digit sum = 2 + 9 + 0 = 11 ✔. Apply to 735 * 5: 735 ÷ 5 = 147; digit sum = 1 + 4 + 7 = 12.Verification / Alternative check:Alternative hypotheses (sum of digits plus/minus the second operand, product of digits, etc.) fail to satisfy both given examples, whereas the “divide then digit-sum” rule works consistently.
Why Other Options Are Wrong:05, 03, or 16 do not match the consistent rule validated by both provided instances.
Common Pitfalls:Jumping to ad-hoc rules that fit only one of the examples. Always verify against all given calibrators before applying to the target case.
Final Answer:12.
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