Correct Answer: A

Rationale: To find the ratio of women to the total number of students, you need to simplify the ratio of 16:28. By dividing both numbers by the greatest common factor, which is 4, you get 4:7. Therefore, the correct ratio of women to the total number of students is 4:7. Choice A is correct. Choices C and D are incorrect because they do not represent a valid ratio. Choice B is the original ratio given in the question, which should be simplified to 4:7 as explained in the rationale.

Correct Answer: B

Rationale: To calculate the percentage of her earnings that Jill saved, divide the amount saved ($140) by the total earnings ($400) and then multiply by 100 to find the percentage. Therefore, (140/400) * 100 = 35%. Jill saved 35% of her earnings. Choice A (30%) is incorrect because it underestimates the percentage saved. Choice C (40%) is incorrect as it overestimates the percentage saved. Choice D (25%) is incorrect for the same reason. The correct calculation is 140/400 = 0.35 * 100 = 35%.

Correct Answer: B

Rationale: To find the total number of balls needed to make the yellow balls 65% of the total, let x be the total number of balls required. Initially, there are 15 yellow balls. The total number of balls would be 15 + x after adding more yellow balls. The equation to represent this is: (15 + x) / (15 + x) = 0.65 (since the yellow balls need to constitute 65% of the total). Solving this equation gives x = 50, indicating that 50 more yellow balls need to be added to the basket to reach the desired percentage. Choice A, C, and D are incorrect as they do not accurately represent the additional yellow balls needed to achieve the specified percentage.

Correct Answer: C

Rationale: In the first scenario, for 43 customers served, the server broke 2 glasses and slipped 5 times. This means for each customer served, the server broke 2/43 glasses and slipped 5/43 times. The information about breaking 10 glasses the next day is irrelevant to the number of customers served. Therefore, to find out the total number of customers served, we calculate 43 customers * (2 glasses/customer + 5 slips/customer) = 86. Choice A, 25, is incorrect as it does not consider the total number of glasses broken or slips. Choice B, 43, is incorrect because it only considers the initial number of customers. Choice D, 215, is incorrect as it miscalculates the relationship between customers, glasses broken, and slips.

Correct Answer: A

Rationale: To convert meters to millimeters, you multiply by 1000 since there are 1000 millimeters in 1 meter. Therefore, 5 meters multiplied by 1000 equals 5000 millimeters. Choice A is correct as it represents the accurate conversion from meters to millimeters. Choices B, C, and D are incorrect as they do not provide the correct conversion factor from meters to millimeters.