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: First, convert the mixed number 1 (1/8) into an improper fraction: 1 (1/8) = 9/8. Now, simplify the expression: (1/4) (3/5) · (9/8). To divide by a fraction, multiply by its reciprocal: (1/4) (3/5) (8/9) = 24/180 = 2/15. Thus, the simplified expression is 2/15. Choice A (8/15) is incorrect because the correct answer is 2/15. Choice B (27/160) is incorrect as it is not the result of the given expression. Choice D (27/40) is incorrect as it does not match the simplified expression obtained.

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.

Correct Answer: C

Rationale: To find the distance traveled by the train, we use the formula Distance = Speed x Time. Given that the train travels at 60 miles per hour for 2 hours, the calculation would be 60 miles/hour x 2 hours = 120 miles. Therefore, the correct answer is 120 miles. Choice A (60 miles) is incorrect because it only represents the speed of the train, not the total distance traveled. Choice B (100 miles) is incorrect as it does not account for the full 2 hours of travel. Choice D (200 miles) is incorrect as it overestimates the distance by multiplying the speed by the time incorrectly.