Correct Answer: C

Rationale: To find the total amount contributed, you can add the individual contributions: $12.03 + $11.96 + $12.06 = $36. Therefore, the roommates used a total of $36 to purchase the gift. Choice A ($34), B ($35), and D ($37) are incorrect as they do not reflect the accurate total amount contributed by the roommates.

Correct Answer: D

Rationale: To solve the equation 2x + 4 = x - 6, first, subtract x from both sides to get x + 4 = -6. Then, subtract 4 from both sides to isolate x, resulting in x = -10. Therefore, the correct answer is x = -10. Choice A is incorrect as it does not follow the correct steps of solving the equation. Choice B is incorrect as it is the result of combining x terms incorrectly. Choice C is incorrect as it is not the correct result of solving the equation step by step.

Correct Answer: C

Rationale: To determine the number of correct answers Mathew needs, solve the inequality: 3x > 96. This simplifies to x > 32. Therefore, Mathew must answer more than 32 questions correctly to qualify for varsity sports. Since the test consists of 40 questions, he can afford to answer at most 40 - 32 = 8 questions incorrectly. Therefore, the correct answer is 0 ≤ x < 8. Option A (x > 32) is incorrect as it suggests Mathew needs to answer more than 32 questions correctly, which is not the case. Option B (x > 8) is also incorrect as it does not account for the total number of questions in the test. Option D (0 ≤ x ≤ 8) is incorrect as it includes the possibility of answering all questions incorrectly, which is not allowed for Mathew to qualify for varsity sports.

Correct Answer: A

Rationale: To solve the expression, first calculate the multiplication: (3)(-4) = -12 and (3)(4) = 12. Then, substitute the results back into the expression: (-12) + 12 - 1 = -1. Therefore, the correct answer is A. Choices B, C, and D are incorrect as they do not result from the correct calculations of the given expression.

Correct Answer: C

Rationale: The ratio of 4:2 simplifies to 2:1. This means that for every 2 algebra problems, there is 1 data analysis problem. If there are 18 algebra problems, we can set up a proportion: 2 algebra problems correspond to 1 data analysis problem. Therefore, 18 algebra problems correspond to x data analysis problems. Solving the proportion, x = 18 * 1 / 2 = 9. Hence, there are 9 data analysis problems on the test. Therefore, the total number of data analysis problems on the test is 18 (algebra problems) + 9 (data analysis problems) = 27.