Correct Answer: D

Rationale: To solve the equation for x, follow these steps: 2x - 7 = 3. Add 7 to both sides to isolate 2x, resulting in 2x = 10. Then, divide by 2 on both sides to find x, which gives x = 5. Therefore, the correct answer is x = 5. Choices A, B, and C are incorrect because they do not accurately solve the equation.

Correct Answer: B

Rationale: To estimate the total number of pounds of potatoes on the farmer's trailer, we can use the average weight of a bag of potatoes. The average weight is calculated by adding the minimum and maximum weights of the bags and dividing by 2: (23 + 27) / 2 = 25 pounds. Next, multiply the average weight by the total number of bags: 25 pounds/bag * 150 bags = 3,750 pounds. Therefore, the best estimate of the total number of pounds of potatoes on the farmer's trailer is 3,750 pounds. Choice A (3,000 pounds) is too low as it underestimates the total weight. Choice C (4,100 pounds) and Choice D (5,000 pounds) are too high as they overestimate the total weight.

Correct Answer: A

Rationale: The distance traveled by the bike in one complete roll of the tire is equal to the circumference, which can be calculated using the formula C = πd, where d is the diameter. Given that the diameter of the bike tire is 27 inches, the circumference is obtained by multiplying the diameter by π. As the tire rolls from the first mark to the fourth mark, it completes three full rotations (one complete roll plus two more). Therefore, the total distance rolled is 3 times the circumference, which results in 3(27π). Choice A is correct. Choice B is incorrect as it incorrectly multiplies the diameter by 4π instead of multiplying the circumference by 4. Choices C and D are incorrect as they involve dividing the diameter by a number, which is not applicable in this context.

Correct Answer: D

Rationale: On a 1:100 scale drawing, each centimeter represents one meter. The area of the room in the scale drawing is 30 cm², which means the actual area is 30 m². Choice A (30,000 cm²) is incorrect as it doesn't account for the scale conversion. Choice B (300 m²) is incorrect because it multiplies the scale area directly by 10,000, which is not the correct conversion. Choice C (3,000 m²) is also incorrect as it applies the scale factor incorrectly.

Correct Answer: C

Rationale: To find the approximate percentage of the times Cora did not slip and fall, subtract the times she fell (20) from the total times around the rink (27), which gives 7. Then, divide the number of times she did not slip and fall (7) by the total times around the rink (27) and multiply by 100 to get the percentage. So, 7 divided by 27 equals 0.259, which rounds to approximately 26%. Therefore, the correct answer is 26%. Choice A (37%) is incorrect because it does not reflect the calculation based on the given information. Choice B (74%) is incorrect as it is not the result of the correct calculation. Choice D (15%) is incorrect as it does not match the calculated percentage based on the scenario provided.