Kimberley earns $10 an hour babysitting, and after 10 p.m., she earns $12 an hour, with the amount paid being rounded to the nearest hour accordingly. On her last job, she worked from 5:30 p.m. to 11 p.m. In total, how much did Kimberley earn on her last job?

Correct Answer: C

Rationale: Kimberley worked from 5:30 p.m. to 11 p.m., which is a total of 5.5 hours before 10 p.m. (from 5:30 p.m. to 10 p.m.) and 1 hour after 10 p.m. The earnings she made before 10 p.m. at $10 an hour was 5.5 hours * $10 = $55. Her earnings after 10 p.m. for the rounded hour were 1 hour * $12 = $12. Therefore, her total earnings for the last job were $55 + $12 = $67. Since the amount is rounded to the nearest hour, the closest rounded amount is $62. Therefore, Kimberley earned $62 on her last job. Choice A is incorrect as it does not consider the additional earnings after 10 p.m. Choices B and D are incorrect as they do not factor in the hourly rates and the total hours worked accurately.

Correct Answer: A

Rationale: To solve 2 x + 8 = 0 2x+8=0: Subtract 8 from both sides: 2 x = − 8 2x=−8 Divide both sides by 2: x = − 8 2 = − 4 x= 2 −8 ​ =−4 Therefore, the solution is x = − 4 x=−4.

Correct Answer: C

Rationale: To determine the number of questions the student solved correctly, we need to calculate 85% of the total number of questions. This can be done by multiplying the total number of questions by 85%, which is 20 questions x 85% = 20 x 0.85 = 17 questions. Therefore, the student solved 17 questions correctly. Choice A, 15, is incorrect as it does not reflect the correct percentage of questions solved. Choice B, 16, and Choice D, 18, are also incorrect as they do not match the calculation based on the given percentage.

Correct Answer: C

Rationale: The formula for the perimeter of a rectangle is P = 2(l + w), where P is the perimeter, l is the length, and w is the width. Given that the total perimeter is 36 cm and each side's length is 12 cm, we substitute the values into the formula: 36 = 2(12 + w). Solving for w gives us w = 6. Therefore, the width of the rectangle is 6 cm. Choice A (3 cm) is incorrect because the width is not half of the length. Choice B (12 cm) is the length, not the width. Choice D (8 cm) is incorrect as it does not match the calculated width of 6 cm.

Correct Answer: A

Rationale: Among the provided options, 0.45 is the largest number. To determine the largest number, compare the decimal values directly. 0.45 is greater than 0.313, 0.3, and 0.096. Therefore, 0.45 is the correct answer. Choice B (0.096) is the smallest as it has the lowest decimal value. Choice C (0.3) is greater than 0.096 but smaller than both 0.313 and 0.45. Choice D (0.313) is greater than 0.3 and 0.096 but smaller than 0.45, making it incorrect.

Correct Answer: A

Rationale: The relative error is calculated using the formula: (|Measured Value - True Value| / True Value) * 100%. Substituting the values given, we have (|36 - 75| / 75) * 100% = (39 / 75) * 100% ≈ 0.52 * 100% = 0.52%. Therefore, the relative error in measurement is approximately 0.52%. Choice A is correct because it reflects this calculation. Choice B is incorrect as it represents a lower relative error than the actual value obtained. Choice C is incorrect as it overestimates the relative error. Choice D is incorrect as it underestimates the relative error.

Correct Answer: D

Rationale: A pie chart is the most appropriate choice for displaying the percentages of time spent on different tasks during the workday because it visually represents parts of a whole. In this case, each task's percentage represents a part of the entire workday, making a pie chart an ideal way to compare these percentages. Line plots, bar graphs, and line graphs are not suitable for showing percentages of a whole; they are more commonly used for tracking trends, comparing values, or showing relationships between variables but do not efficiently represent parts of a whole like a pie chart does.

Correct Answer: B

Rationale: The difference between Alan's current weight of 200 pounds and his goal weight of 175 pounds is 25 pounds (200 pounds - 175 pounds). To convert pounds to kilograms, you multiply the number of pounds by 0.45 (not divide by 2.2). Thus, 25 pounds is approximately 11.25 kilograms (25 pounds x 0.45). Therefore, the difference in kilograms is 11.25 kg. Choice A is incorrect because it miscalculates the conversion. Choices C and D are significantly higher values and do not reflect the correct conversion from pounds to kilograms.

Correct Answer: D

Rationale: Xavier starts with 20 apples. He gives half of his apples to his sister Emma, which is 20 · 2 = 10 apples, leaving him with 10 apples. Then, he gives 6 apples to his neighbor Jim, leaving him with 10 - 6 = 4 apples. Using ¾ of his remaining 4 apples for the pie, he uses 3/4 x 4 = 3 apples. Therefore, he has 4 - 3 = 1 apple left at the end of the day. Choice D, 1 apple, is the correct answer. Choices A, B, and C are incorrect because Xavier ends up with 1 apple remaining, not 4, 6, or 2.