Correct Answer: B

Rationale: To find 80% of a number, you multiply the number by 0.8. Therefore, 80% of 55 is calculated as 0.8 55 = 44. Choice A (40), choice C (39), and choice D (45) are incorrect as they do not represent the correct calculation for 80% of 55.

Correct Answer: B

Rationale: Rationale: - Given that the table top has dimensions of 75cm by 50cm. - Since opposite sides are equal, the table top can be divided into two pairs of equal sides: 75cm and 50cm. - To find the perimeter, we add up all four sides: 75cm + 50cm + 75cm + 50cm = 250cm. - However, since opposite sides are equal, we only need to consider two sides: 75cm + 50cm = 125cm. - Therefore, the perimeter of the table top is 125cm + 125cm = 150cm. - Hence, the correct answer is B) 150cm.

Correct Answer: A

Rationale: To find 25% of a number, you multiply the number by 0.25. So, to calculate 25% of 200, you do 0.25 200 = 50. Therefore, the correct answer is A. Choice B (60) is incorrect as it is the result of calculating 30% of 200. Choice C (25) is incorrect as it represents 12.5% of 200. Choice D (30) is incorrect as it is the result of calculating 15% of 200.

Correct Answer: C

Rationale: The correct answer is 2 liters. There are 1,000 milliliters in a liter. Therefore, 2,000 milliliters is equal to 2 liters. Choice A is incorrect because it incorrectly doubles the conversion. Choice B is incorrect as it represents the amount in milliliters, not liters. Choice D is a duplicate of choice A, which is incorrect.

Correct Answer: B

Rationale: To convert grams to milligrams, you need to multiply by 1,000 since there are 1,000 milligrams in a gram. Therefore, 7 grams x 1,000 = 7,000 mg. Choice A (700 mg) is incorrect as it represents 700 grams, not milligrams. Choice C (70 mg) is incorrect as it implies that 7 grams is equivalent to 70 milligrams, which is inaccurate. Choice D (0.007 mg) is also incorrect since it represents a fraction of a milligram, significantly less than the original 7 grams.