A tea seller bought 15 kg of Darjeeling tea at ₹300 per kg and 25 kg of Assam tea at ₹240 per kg. He mixed them together. Due to a slight drop in market prices, he had to sell the entire mixture at ₹260 per kg. Calculate his total profit or loss.

Shortcut Trick Calculate the net profit or loss per unit directly using individual deviations from the final Selling Price: Loss on Darjeeling tea = (300 − 260) = ₹40/kg ⇒ Total = 15 × 40 = ₹600 (Loss) Profit on Assam tea = (260 − 240) = ₹20/kg ⇒ Total = 25 × 20 = ₹500 (Profit) Net overall effect = 500 (Profit) − 600 (Loss) = −100 (Net Loss) ∴ The correct answer is Loss of ₹100. Alternate Method Given: Quantity of Darjeeling tea = 15 kg at ₹300/kg Quantity of Assam tea = 25 kg at ₹240/kg Selling price of the entire mixture = ₹260/kg Formula Used: Total Cost Price (CP) = Sum of (Quantity × Rate per kg) Total Selling Price (SP) = Total Quantity × SP per kg Profit or Loss = Total SP − Total CP Darjeeling Tea 15 kg × ₹300 = ₹4500 Assam Tea 25 kg × ₹240 = ₹6000 Total CP = ₹10500 Loss = ₹100 40 kg × ₹260 Total SP = ₹10400 Calculations: ⇒ Total CP of Darjeeling tea = 15 × 300 = ₹4500 ⇒ Total CP of Assam tea = 25 × 240 = ₹6000 ⇒ Total Cost Price (CP) of the mixture = 4500 + 6000 = ₹10500 ⇒ Total quantity of the mixture = 15 + 25 = 40 kg ⇒ Total Selling Price (SP) of the mixture = 40 × 260 = ₹10400 ⇒ Since Total CP > Total SP, the seller incurs a loss. ⇒ Loss = Total CP − Total SP = 10500 − 10400 = ₹100 ∴ The correct answer is Loss of ₹100. Additional Information Alligation Method Used to find the ratio in which two ingredients are mixed to produce a mixture of a desired mean price. The ratio of quantities is inversely proportional to the differences in their prices from the mean price. Weighted Average To find the mean price directly without calculating overall totals, use the formula: Mean Price = (Q 1 × P 1 + Q 2 × P 2 ) ÷ (Q 1 + Q 2 ). Profit and Loss Percentage Profit % = (Profit ÷ Total CP) × 100. Loss % = (Loss ÷ Total CP) × 100. Both are always calculated on the total Cost Price unless specifically mentioned otherwise.