Mathematics

When the price of a toy is increased by 20%, the new price factor is 1.20. When the number of toys sold decreases by 15%, the new quantity factor is 0.85. The overall effect on sales revenue is the product of these two factors: 1.20 × 0.85 = 1.02, which means a 2% increase in sales revenue. Therefore, the sales revenue increases by 2%, corresponding to option C.

The friend sells the car for Rs. 54,000 at a 20% gain, so the friend's cost price is Rs. 54,000 / 1.20 = Rs. 45,000. This Rs. 45,000 is the price at which the original man sold the car at a 10% loss, so the original cost price is Rs. 45,000 / 0.90 = Rs. 50,000. However, this calculation shows Rs. 50,000, which corresponds to option C, but the question asks for the original cost price of the car, which is Rs. 50,000. Therefore, the correct answer is C.

The cost price (CP) of the article can be calculated using the selling price (SP) and profit percentage: CP = SP / (1 + profit%) = 800 / 1.25 = Rs.640. To make a loss of 25%, the selling price should be SP = CP × (1 - loss%) = 640 × 0.75 = Rs.480. Therefore, the shopkeeper should sell the article at Rs.480 to incur a 25% loss, which corresponds to option B.

Let the marked price be M and cost price be C. Given selling price after 15% discount is 6800, so 0.85M = 6800 => M = 8000. Selling at marked price gives 60% profit, so M = 1.6C => 8000 = 1.6C => C = 5000. Hence, the cost price is Rs. 5000.

Since the cost price (C.P) is 40% of the selling price (S.P), the selling price is 100% of itself. To find what percent the S.P is of the C.P, we calculate (S.P / C.P) × 100 = (100% / 40%) × 100 = 250%.

Initially, profit is 320% of cost, so selling price = cost + profit = 100% + 320% = 420% of cost. When cost increases by 25%, new cost = 125% of original cost, but selling price remains 420% of original cost. New profit = selling price - new cost = 420% - 125% = 295% of original cost. To find profit as a percentage of selling price: (295% / 420%) × 100% ≈ 70%.

The cost price per article is Rs. 25/15 = Rs. 5/3. The selling price per article is Rs. 30/12 = Rs. 2.5. Profit per article = 2.5 - 5/3 = 2.5 - 1.6667 = 0.8333. Profit percentage = (0.8333 / 1.6667) × 100 = 50%. However, this calculation seems off; let's re-check carefully: Cost price for 15 articles = Rs. 25, so cost price per article = 25/15 = Rs. 1.6667. Selling price for 12 articles = Rs. 30, so selling price per article = 30/12 = Rs. 2.5. Profit per article = 2.5 - 1.6667 = 0.8333. Profit percentage = (0.8333 / 1.6667) × 100 = 50%. So the profit percentage is 50%, which matches option B. Therefore, the correct answer is B.

First, calculate the cost price per kg of the mixture: ((24 kg × Rs.150) + (36 kg × Rs.125)) / (24 + 36) = (3600 + 4500) / 60 = Rs.135 per kg. To make a 40% profit, selling price = 135 × 1.40 = Rs.189 per kg.

The price decreased by 20%, so the new price is 80% of the original. The quantity sold increased by 40%, so the new quantity is 140% of the original. The new sales amount is 0.8 × 1.4 = 1.12, which is a 12% increase in sales.

The marked price is 10% above cost price, so marked price = 110% of cost price. The trader suffers a 1% loss, so selling price = 99% of cost price. The discount = (marked price - selling price) / marked price = (110% - 99%) / 110% = 11% / 110% = 10.0%. However, this calculation shows 10%, but let's verify carefully: Selling price = 99% of cost price; Marked price = 110% of cost price; Discount = (110% - 99%) / 110% = 11% / 110% = 10%. So discount is 10%. But the options include 10% as A and 10.5% as B. The correct discount is 10%, so option A is correct. Therefore, the original correct_answer 'A' is correct. Explanation updated accordingly.