Correct Answer: A

Rationale: To find the full RDI, divide the amount of protein consumed (75 grams) by 30% (or 0.30): 75 · 0.30 = 250 grams. Therefore, the person needs 250 grams of protein to meet the full RDI. Choice A is correct because it accurately calculates the amount needed to reach the full RDI. Choices B, C, and D are incorrect as they do not correctly calculate the total amount of protein needed based on the given information.

Correct Answer: A

Rationale: To solve x:15=120:225, set it up as a proportion: x/15 = 120/225. Simplify the right-hand side: 120/225 = 8/15. Now, solve for x by cross-multiplying: x = 8. Therefore, the correct answer is A. Choices B, C, and D are incorrect as they do not align with the correct calculations.

Correct Answer: A

Rationale: To find how much more water is needed, subtract 1/3 cup from 4/5 cup. First, find a common denominator: The least common denominator between 5 and 3 is 15. Convert the fractions: 4/5 = 12/15, 1/3 = 5/15. Now, subtract: 12/15 - 5/15 = 7/15. Therefore, you need to add 7/15 cups of water. Choice B (2/3 cups) is incorrect because it does not represent the correct amount of additional water needed. Choice C (1/3 cups) is incorrect because this is the amount of water that was accidentally added. Choice D (1/15 cups) is incorrect as it does not reflect the correct calculation of the additional water required.

Correct Answer: C

Rationale: To find the volume of the frustum of a cone, divide it into two cones and calculate their volumes separately. The formula for the volume of a cone frustum involves the radii of both bases and the height. The volume of the frustum cone can be calculated as V = 1/3 * π * h * (R^2 + r^2 + R * r), where R is the larger radius, r is the smaller radius, and h is the height. Substituting the values, V = 1/3 * π * 15 * (10^2 + 20*10 + 20^2) = 1875 cu cm. Therefore, the correct answer is 1875 cu cm. Choice A, B, and D are incorrect as they do not correspond to the correct calculation of the frustum's volume.

Correct Answer: D

Rationale: To find the total number of days Bill will have off, add his vacation days and sick days together. Bill has 2.5 vacation days and 1.25 sick days: 2.5 + 1.25 = 3.75 days When rounding to the nearest whole number, 3.75 rounds up to 4. Therefore, Bill will have 4 days off work.