1. Identify the original price: $400. 2. Identify the discount percentage: 15%. 3. Calculate the discount amount: 15% of $400 = (15/100) * $400 = $60. 4. Subtract the discount amount from the original price to find the final price: $400 - $60 = $340. Why others are wrong: A — Correct answer. B — This results from calculating a 10% discount ($40) instead of a 15% discount. C — This results from subtracting the percentage number (15) directly from the price ($400 - 15), instead of the percentage value. D — This results from adding the discount amount ($60) to the original price instead of subtracting it.

1. Identify the number of croissants sold: 60. 2. Identify the total number of items sold: 240. 3. To find the percentage, divide the number of croissants by the total items and multiply by 100. 4. Calculation: (60 / 240) * 100. 5. Simplify the fraction: (1 / 4) * 100. 6. Perform the multiplication: 25%. Why others are wrong: A — This would be the percentage if 48 items were croissants (48/240 = 0.2). B — This is the correct calculation. C — This would be the percentage if 72 items were croissants (72/240 = 0.3). D — This would be the percentage if 96 items were croissants (96/240 = 0.4).

Step 1: Calculate the number of employees in the sales department. Number of sales employees = 40% of 250 Number of sales employees = (40/100) * 250 = 0.40 * 250 = 100 employees. Step 2: Calculate the number of new hires within the sales department. Number of new hires in sales = 20% of the sales employees Number of new hires in sales = 20% of 100 Number of new hires in sales = (20/100) * 100 = 0.20 * 100 = 20 employees. Why others are wrong: A — Correct calculation. B — This is the result of miscalculating the final percentage (e.g., taking 20% of 50 instead of 100, or taking 4% of 250). C — This is the result of incorrectly applying the new hire percentage (20%) to the total number of employees (20% of 250). D — This is the total number of employees in the sales department, not the specific number of new hires within that department.

1. Calculate the total number of fiction books: 40% of 12,000 = 0.40 * 12,000 = 4,800 books. 2. Calculate the number of science fiction books (which are a subset of fiction): 30% of 4,800 = 0.30 * 4,800 = 1,440 books. 3. To find the number of books NOT classified as science fiction, subtract the number of science fiction books from the total number of books: 12,000 - 1,440 = 10,560 books. Why others are wrong: A — This is the number of science fiction books, not the number of books that are NOT science fiction. B — This is the number of fiction books that are NOT science fiction (4,800 - 1,440 = 3,360), but it excludes all non-fiction books. C — This is the number of non-fiction books (12,000 - 4,800 = 7,200), but it excludes the fiction books that are not science fiction. D — This is the correct calculation of total books minus science fiction books.

1. Assume an initial revenue in December, for example, $100. 2. Calculate the revenue after a 15% increase in January: $100 * (1 + 0.15) = $115. 3. Calculate the revenue after a 15% decrease from the January value in February: $115 * (1 - 0.15) = $97.75. 4. Determine the absolute change from the original December revenue: $97.75 - $100 = -$2.25. 5. Calculate the overall percentage change: (-$2.25 / $100) * 100% = -2.25%. 6. This represents a 2.25% decrease. Why others are wrong: A — This common misconception assumes the 15% decrease is applied to the original December value, effectively cancelling out the increase. B — Incorrectly calculates the overall change as an increase rather than a decrease. D — Represents an arithmetic error in the calculation of the final percentage change.