Correct Answer: B

Rationale: To find the range where n lies when n = 8, we consider numbers greater and lesser than 8. The range would be between 7 and 9, not 9 and 11 as stated in the original rationale. Option A (5 and 7) and Option D (3 and 5) are lower ranges, while Option C (9 and 11) exceeds the upper limit.

Correct Answer: B

Rationale: To find the range where n lies when n = 8, we consider numbers greater and lesser than 8. The range would be between 7 and 9, not 9 and 11 as stated in the original rationale. Option A (5 and 7) and Option D (3 and 5) are lower ranges, while Option C (9 and 11) exceeds the upper limit.

Correct Answer: A

Rationale: To find the number that 20 is equal to 40% of, you can set up the equation: 20 = 0.4 * x, where x is the unknown number. To solve for x, divide both sides of the equation by 0.4. This gives x = 20 / 0.4 = 50. Therefore, 20 is 40% of 50. Choice B, 8, is incorrect because 20 is not equal to 40% of 8. Choice C, 200, is incorrect because 20 is not equal to 40% of 200. Choice D, 5000, is incorrect because 20 is not equal to 40% of 5000. The correct answer is 50.

Correct Answer: A

Rationale: The domain of a function consists of all possible input values that produce a valid output. In the case of y = 1/x, the function is undefined when x = 0 because division by zero is not defined in mathematics. Therefore, the correct domain for y = 1/x is all real numbers except 0 (Choice A). Choice B, x > 0, is incorrect because it excludes the value x = 0. Choice C, x = 0, is also incorrect as x = 0 is not a valid part of the domain due to the function being undefined at this point. Choice D, x = 1, is unrelated to the domain of the function and does not represent the set of valid input values for y = 1/x.

Correct Answer: D

Rationale: Xavier gives away half of his 20 apples (10), then gives 6 more apples, leaving him with 4 apples. He uses 3/4 of the remaining 4 apples (3) for the pie, leaving him with 1 apple at the end of the day. Therefore, the correct answer is 1. Choices A, B, and C are incorrect because they do not accurately reflect the calculations of apples given away and used for the pie, resulting in the remaining amount of 1 apple.