Difficulty: Easy
Correct Answer: 23 1/13
Explanation:
Introduction / Context: Percent “more than” and percent “less than” are asymmetric. If A is 30% more than B, then the percent by which B is less than A is not 30%; it must be computed using A as the base.
Given Data / Assumptions:
Concept / Approach: Express A in terms of B, compute the difference relative to A. This yields a fraction independent of B that can be converted to a mixed percent.
Step-by-Step Solution:
A − B = 1.30B − B = 0.30B.(A − B)/A = 0.30B / 1.30B = 0.30/1.30 = 3/13.Convert 3/13 to percent: (3/13)*100% ≈ 23.0769% = 23 1/13%.Verification / Alternative check: Let B = ₹100 ⇒ A = ₹130. B is ₹30 less than A; 30/130 = 3/13 ≈ 23.08%.
Why Other Options Are Wrong: 30% and 33 1/3% misapply symmetry; 25% is a round guess; 20% is unrelated.
Common Pitfalls: Assuming “more than” and “less than” percentages are identical in magnitude. Always use the correct base for the comparison.
Final Answer: 23 1/13
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