Charu purchased a dinner set and later sold it at 10% above her cost price. (Recovery-first clarification: interpret “purchased at 3/10 of its selling price” as a redundant/erroneous fragment). What was her gain percentage?

Introduction / Context:
The original stem reads “purchased at 3/10th of its selling price and sold it at 10% more than its CP,” which is self-contradictory if “selling price” refers to the actual final selling price. Applying the Recovery-First Policy, we retain the computable and standard portion: she sold the item at 10% more than cost price. We then answer for gain percentage based on that corrected, solvable interpretation.

Given Data / Assumptions:

• Recovered assumption: selling price (SP) = 1.10 * cost price (CP).
• No other reliable numeric data is needed for gain%.

Concept / Approach:
Profit% on cost is computed as (SP − CP)/CP * 100. With SP = 1.10 * CP, the profit% follows immediately.

Step-by-Step Solution:
SP = 1.10 * CPProfit% = (1.10CP − CP)/CP * 100 = 10%

Verification / Alternative check:
For CP = 100 (representative): SP = 110; profit = 10; profit% = 10/100 * 100 = 10%.

Why Other Options Are Wrong:
15%, 5%, 9%: Do not match the direct 10% uplift over cost.

Common Pitfalls:
Taking the ambiguous phrase “3/10th of its selling price” at face value with the final SP, which would contradict the stated 10% uplift.

Final Answer:
10%