Profit and Loss – Short weight with stated price gain: A seller uses a 920 g weight in place of 1 kg and also sells at a 15% gain on cost price. What is his actual overall profit percentage?

Introduction / Context:
Short weight inflates the effective selling price per true kilogram, and a nominal price gain compounds the effect. Convert both influences to multiplicative factors to find the true overall gain percentage.

Given Data / Assumptions:

• Uses 920 g instead of 1000 g (1 kg)
• Advertised price gain = 15%

Concept / Approach:
Short weight factor = 1000 / 920. Price factor = 1.15. Overall multiplier = 1.15 * (1000/920). The net gain percentage equals (overall multiplier − 1) * 100.

Step-by-Step Solution:
Short weight factor ≈ 1.086956Overall = 1.15 * 1.086956 ≈ 1.25Profit% ≈ (1.25 − 1) * 100 = 25%

Verification / Alternative check:
Per true kg, revenue becomes 15% higher and then further scaled by 1000/920 ≈ 1.086956, giving 1.25 overall—an exact 25% gain.

Why Other Options Are Wrong:
20% and 18% are too low; 30% is too high; 15% ignores the short-weight advantage.

Common Pitfalls:
Adding 15% and 8.6956% directly rather than multiplying factors.

Final Answer:
25%