Correct Answer: B

Rationale: To find the approximate number of people who voted for the proposition, multiply the town's population by the percentage that voted for it. 9.5% of 51,623 is about 0.095 * 51,623 ≈ 4,904. Rounded to the nearest thousand, this gives an estimate of 5,000 people. Therefore, choice B, '5,000,' is the correct answer. Choices A, C, and D are incorrect as they do not align with the calculated estimation.

Correct Answer: B

Rationale: To find out how many tanks of gas Robert needs for the 1,800-mile trip, first, we calculate the distance his car can travel on a full tank: 30 miles per gallon 12 gallons = 360 miles per tank. Next, divide the total trip distance by the distance per tank: 1,800 miles · 360 miles per tank = 5 tanks. Therefore, Robert will need 5 tanks of gas to complete the cross-country trip. Choices A, C, and D are incorrect as they do not accurately calculate the number of tanks needed based on the given information.

Correct Answer: A

Rationale: To simplify the expression 5 x 3 · 9 x 4, first perform the multiplications and divisions from left to right: 5 x 3 = 15 and 9 x 4 = 36. So, the expression becomes 15 · 36. When dividing fractions, multiply the first fraction by the reciprocal of the second fraction. Hence, 15 · 36 = 15/36. To simplify the fraction further, find the greatest common divisor, which is 3. Divide both the numerator and denominator by 3 to get the final result: 15/36 = 5/12. Therefore, the correct answer is A. Choices B, C, and D are incorrect because they do not represent the correct simplification of the given expression.

Correct Answer: C

Rationale: The correct answer is C. Group B is negatively skewed, indicating more high scores, leading to a higher mean for Group B when compared to Group A. Choice A is incorrect because Group A is not negatively skewed and doesn't have a mean less than Group B. Choice B is incorrect as Group A is not positively skewed and its mean is not greater than Group B. Choice D is also incorrect because Group B having a mean less than Group A contradicts the fact that Group B has a higher mean due to being negatively skewed.

Correct Answer: B

Rationale: During January, Dr. Lewis worked 20 shifts. Shifts for January = 20. During February, she worked three times as many shifts as she did during January. Shifts for February = (20)(3) = 60. During March, she worked half the number of shifts she worked in February. Shifts for March = (60)(1/2) = 30. Therefore, the correct equation to describe the number of shifts Dr. Lewis worked in March is 'shifts = (20)(3)(1/2)', representing the calculation based on the given scenario. Choices A, C, and D do not accurately represent the correct mathematical relationship between the shifts worked in the different months, making them incorrect.