If A runs less fast than B, and B runs as fast but not faster than C; then, as compared to A, C runs
- (a) slower than A
- (b) faster than A ✓ UPSC's answer
- (c) with same speed as A
- (d) Given data is not sufficient to determine
Why the answer is (b)
• The statement 'A runs less fast than B' establishes the inequality A < B.
• The statement 'B runs as fast but not faster than C' means B is not slower than C and not faster than C, implying B = C.
• Substituting C for B in the first inequality gives A < C.
• Therefore, C runs faster than A.
• This logical deduction confirms that option (b) is the correct answer.
Why the other options are wrong
- (a) slower than A
- This option contradicts the derived relationship A < C, which means C is faster, not slower, than A.
- (c) with same speed as A
- This option is incorrect because A is explicitly stated to run less fast than B, and since B equals C, A cannot run at the same speed as C.
- (d) Given data is not sufficient to determine
- The data is sufficient because the transitive property of speed comparisons allows a definitive conclusion that C is faster than A.
Asked in the CSAT Paper II of the UPSC Civil Services Preliminary Examination 2015, held on 23 August 2015. Question and answer key: Union Public Service Commission. Explanation: UPSC Answer Check.