Enrollment comparison puzzle: Class A has a higher enrollment than Class B, and Class C has a lower enrollment than Class B; assess whether the statement "Class A has a lower enrollment than Class C" must be true given only these two premises.
Logical Reasoning
Logical Problems
Difficulty: Medium
Choose an option
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ADefinitely true
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BDefinitely false
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CCannot be determined from the given premises
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DTrue only if the differences are small
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ETrue only if the enrollments are consecutive numbers
Answer
Correct Answer: Definitely false
Explanation
Given data
- Premise 1: A > B (Class A has higher enrollment than Class B).
- Premise 2: C < B (Class C has lower enrollment than Class B).
- Claim to test: A < C.
Concept / ApproachChain inequalities around B and derive the relative order between A and C.
Step-by-step reasoningStep 1: From A > B and C < B, we have A on the right of B and C on the left of B on the number line.Step 2: Therefore A > B > C, which implies A > C.Step 3: The claim A < C contradicts A > C derived above, so it cannot be true under any values consistent with the premises.
Verification / Alternative viewExample: Let B=30, A=35 (A>B), C=20 (CC. No choice of numbers that respects the premises will make A
Common pitfalls
- Thinking "both are different from B" leaves A and C incomparable. Here, the directions relative to B determine a strict order.
Final AnswerDefinitely false.