Correct Answer: A

Rationale: To convert a decimal to a percentage, you move the decimal point two places to the right and add a percentage sign. Therefore, 0.608 as a percent is 60.8%. The correct answer is A. Choice B (68%) is incorrect because it represents the percentage for a different decimal value. Choice C (0%) is incorrect as it represents 0 as a percentage, not 0.608. Choice D (6%) is incorrect as it also represents a different decimal value, not 0.608.

Correct Answer: B

Rationale: To solve the proportion 0.1:10=x:400, first, simplify the left side to 1:100. Then, set up the proportion as 1:100=x:400. Cross multiply to get x = 4. Therefore, the correct answer is B. Choice A (5) is incorrect because it does not match the calculated value of x. Choice C (50) is incorrect as it is not the result of solving the proportion provided. Choice D (25) is incorrect as it does not align with the correct calculation of x.

Correct Answer: D

Rationale: To find the volume of a pyramid, we use the formula: Volume = (1/3) * base area * height. First, calculate the base area by squaring the base side length: 10cm * 10cm = 100 sq cm. Substitute the values into the formula: Volume = (1/3) * 100 sq cm * 8cm = 80 cu cm. Therefore, the correct answer is 160 cu cm. Choices A, B, and C are incorrect because they do not correctly calculate the volume of the pyramid based on the given dimensions.

Correct Answer: B

Rationale: To administer 20 mg of the medication, you would need 25 mL. This calculation is derived from the concentration of 4 mg per 5 mL. By setting up a proportion, you can determine that for 20 mg, 25 mL must be administered as follows: (20 mg / 4 mg) = (x mL / 5 mL). Solving for x results in x = 25 mL. Choice A is incorrect because it miscalculates the proportion. Choices C and D are incorrect as they do not account for the correct concentration of the medication.

Correct Answer: A

Rationale: To find out how many gallons are in the tank when it is 3/4 full, you need to calculate 3/4 of 16 gallons. 3/4 of 16 is (3/4) x 16 = 12 gallons. Therefore, the car's gas tank contains 12 gallons when it is 3/4 full. Choice B (8 gallons) is incorrect because that would be 1/2 of the tank's capacity, not 3/4. Choice C (14 gallons) is incorrect as it exceeds the full capacity of the tank. Choice D (10 gallons) is incorrect as it is less than 3/4 of the tank's capacity.