Correct Answer: C

Rationale: To find the mean time, you need to add all the times (22.33 + 22.50 + 22.50 + 22.61 + 22.71 + 22.72 + 22.83 + 23.22) and then divide by the total number of times (8). This calculation results in a mean time of 22.68 seconds. Choice A, 22.50 sec, is incorrect because it is the time of one of the runners, not the mean time. Choice B, 22.66 sec, and Choice D, 22.77 sec, are also incorrect as they are not the calculated mean of the given times.

Correct Answer: A

Rationale: To find the number of students who said their favorite color is blue, we calculate 35% of 100, which is (35/100) * 100 = 35. Therefore, 35 students said their favorite color is blue. Choice B is incorrect because it represents the percentage of students who chose red. Choice C is incorrect as it represents the percentage of students who chose green. Choice D is incorrect as it represents the percentage of students who chose yellow.

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: D

Rationale: To find the total cost of Susan's outfit, you need to add the prices of the dress, shoes, and accessories. $69.99 (dress) + $39.99 (shoes) + $34.67 (accessories) = $144.65. Therefore, the correct answer is $144.65. Option A ($69.99) is incorrect as it only represents the price of the dress. Option B ($75.31) is incorrect as it does not account for the total cost. Option C ($109.98) is incorrect as it does not include the individual prices of all items purchased.

Correct Answer: C

Rationale: Erma receives a 25% discount on the $44 sweater, which amounts to a $11 discount. Therefore, she pays $44 - $11 = $33 for this sweater. Adding this discounted price to the $50 sweater, Erma will spend a total of $50 + $33 = $83. Choice A, $79, is incorrect because it does not include the correct calculation for the discounted sweater. Choice B, $81, is incorrect as it does not consider the discounts on both sweaters. Choice D, $85, is incorrect since it overestimates the total amount Erma will spend.