Oranges are bought at 5 for ₹ 10 and sold at 6 for ₹ 15. The profit or loss as percentage is

### Concept & Formula Profit or loss percentage is determined by comparing the Cost Price (CP) of a single unit with its Selling Price (SP). $$Profit \% = \left( \frac{SP - CP}{CP} \right) \times 100$$ ### Step-by-Step Solution * **Given:** 5 oranges bought for ₹ 10; 6 oranges sold for ₹ 15. * **Calculation:** 1. CP of 1 orange = $\frac{10}{5} = \text{₹ } 2$ 2. SP of 1 orange = $\frac{15}{6} = \text{₹ } 2.5$ 3. Profit = $SP - CP = 2.5 - 2 = \text{₹ } 0.5$ 4. Profit \% = $\left( \frac{0.5}{2} \right) \times 100 = \frac{50}{2} = 25\%$ ### Exam Strategy & Shortcut Equate the number of articles. LCM of 5 and 6 is 30. CP of 30 oranges = $10 \times 6 = 60$ SP of 30 oranges = $15 \times 5 = 75$ Profit = $75 - 60 = 15$ Profit \% = $\left(\frac{15}{60}\right) \times 100 = 25\%$. ### Common Pitfall Students often mix up the numerator and denominator when finding the price per unit, mistakenly calculating $5/10$ instead of $10/5$. Always divide Price by Quantity. ### Final Answer Therefore, the correct answer is **25%**.