A trader mixes 26 kg of rice at Rs. 20 per kg with 30 kg of rice of other variety at Rs. 36 per kg and sells the mixture at Rs. 30 per kg. His profit percent is:

Given Data

• Rice 1: 26 kg @ Rs. 20 per kg
• Rice 2: 30 kg @ Rs. 36 per kg
• Selling price of mixture = Rs. 30 per kg
• Required: overall profit percent on cost

Step 1: Compute total cost and total quantityTotal cost = 26 × 20 + 30 × 36 = 520 + 1080 = Rs. 1,600Total quantity = 26 + 30 = 56 kgAverage cost per kg = 1,600 ÷ 56 = Rs. 28.5714…

Step 2: Profit per kg and profit percentProfit per kg = SP − average CP = 30 − 28.5714… = 1.4286…Profit% on cost = (1.4286… ÷ 28.5714…) × 100 = 0.05 × 100 = 5% profit

Checks & Common Pitfalls

• Use weighted average cost; do not average the two prices arithmetically without weights.
• Ensure per-kg comparison (SP vs average CP) before percentage.

Final AnswerOverall profit = 5% profit.