Logic: 'All squares are rectangles, some rectangles are parallelograms.' Therefore:
Appeared in: AIIMS CRE, SNO-2024
Explanation
The premises establish that squares are a subset of rectangles, and rectangles have some overlap with parallelograms.
This creates a possibility that the area of overlap between rectangles and parallelograms also includes squares, but it does not guarantee it.
The conclusion 'Some squares might be parallelograms' correctly reflects this state of possibility, making it the only logically sound option among the choices.
Why Other Options Were Wrong
Option A: This is an invalid generalization. The premises only state that 'some' rectangles are parallelograms, which provides no information to make a universal claim about all parallelograms.
Option C: This is a conclusion of certainty that cannot be proven from the premises. The premises explicitly allow for the possibility of an overlap between squares and parallelograms.
Option D: This is a logical fallacy known as the 'fallacy of the converse'. It incorrectly reverses the first premise. Just because all squares are rectangles does not mean all rectangles must be squares.
Related Visual
Visual 1: Venn Diagram - A diagram showing three circles for 'Squares', 'Rectangles', and 'Parallelograms'. The 'Squares' circle is shown entirely within the 'Rectangles' circle. The 'Rectangles' circle overlaps with the 'Parallelograms' circle, visually demonstrating the possible (but not certain) intersection between squares and parallelograms.
Clinical Relevance
Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Syllogistic Reasoning and Deductive Logic as background academic context rather than a clinical decision trigger.
Logical reasoning is a core component of the aptitude sections in nursing and other competitive entrance exams, testing a candidate's critical thinking and problem-solving skills.
In clinical practice, nurses use deductive and inductive reasoning daily to interpret patient symptoms, evaluate treatment effectiveness, and prioritize care, avoiding logical fallacies to ensure patient safety.
What if the second premise was 'All rectangles are parallelograms'? In that case, the conclusion would become a certainty: 'All squares are parallelograms.' This is because if squares are a subset of rectangles, and rectangles are a subset of parallelograms, then squares must also be a subset of parallelograms (a transitive property).
How to Approach the Question
Identify the question type as a syllogism, which requires drawing a logical conclusion from two given premises.
Translate each premise into a relationship between sets. 'All A are B' means A is a subset of B. 'Some A are B' means sets A and B have an overlap.
Visualize the relationships, ideally by sketching a quick Venn diagram. Place the 'Squares' circle inside the 'Rectangles' circle, and then make the 'Rectangles' circle overlap with a 'Parallelograms' circle.
Examine your diagram to see what relationships are certain and what are merely possible.
Evaluate each answer choice against your diagram. Eliminate conclusions that make invalid generalizations (e.g., 'all'), state a certainty that isn't guaranteed, or incorrectly reverse a premise (converse fallacy).
Select the option that accurately reflects a possibility or certainty that is directly supported by the premises.
Concept Tested & Keywords
Concept Tested: Syllogistic Reasoning and Deductive Logic
Stem keywords: Logic, All squares are rectangles, some rectangles are parallelograms
Lead-in keywords: Therefore
Negative lead-in flag: false
Question ID
QGJEM2b9z9i6_XMXHDJ9YI
Practise the full AIIMS CRE, SNO-2024
Attempt every question from this paper in a timed mock, then review the full solution for each one.