Bob decides to go into business selling lemonade. He buys a wooden stand for $45 and sets it up outside his house. He figures that the cost of lemons, sugar, and paper cups for each glass of lemonade sold will be 10¢. Which of these expressions describes his cost for making g glasses of lemonade?

Correct Answer: A

Rationale: The cost for making g glasses of lemonade includes the initial cost of the stand ($45) plus 10¢ for each glass of lemonade sold. Therefore, the expression that represents the cost for making g glasses of lemonade is $45 + $0.1 g, which matches option A. Choice B, $44.90 g, is incorrect as it does not account for the initial stand cost of $45. Choice C, $44.90 g + 10¢, is incorrect because it does not include the initial stand cost and incorrectly adds an extra 10¢ for every glass. Choice D, $90, is incorrect as it does not consider the variable cost of 10¢ per glass and only represents the initial stand cost.

Correct Answer: A

Rationale: To simplify the given expression 5x - 2y + 4x + y, we combine like terms. Grouping the x terms together and the y terms together, we have 5x + 4x - 2y + y. Combining like terms results in 9x - y. Therefore, the simplest form of the expression is 9x - y, which corresponds to option A. Option B is incorrect because it incorrectly subtracts 3y instead of just y. Option C is incorrect because it adds 3y instead of subtracting y. Option D is incorrect as it separates x and y with a semicolon instead of an operation, providing no simplified expression.

Correct Answer: B

Rationale: When the woman stacks the two bookcases together, the total height will be the sum of the heights of the two bookcases. Therefore, 14 inches (larger bookcase) + 8 inches (smaller bookcase) = 22 inches. So, the stacked bookcases will be 22 inches tall. Choice A is incorrect because it does not account for the total height of both bookcases. Choice C and D are incorrect as they are higher than the combined height of the two bookcases.

Correct Answer: C

Rationale: To determine how many prizes should be awarded to 5th-grade students, we need to set up the proportion of the number of 5th-grade students to the total number of students in the school. The total number of students is 35 + 38 + 38 + 33 + 36 = 180 students. To find the proportion of 5th-grade students, it would be 36/180 = 0.2. Since there are 20 prizes to be awarded, multiplying 0.2 by 20 gives us 4, which means 4 prizes should go to the 5th-grade students. Therefore, the correct answer is 4. Choice A (5) is incorrect as it does not align with the proportional distribution. Choice B (4) is the correct answer, as calculated. Choice C (7) is incorrect as it exceeds the total number of prizes available. Choice D (3) is incorrect as it does not match the proportional distribution based on the number of students.

Correct Answer: D

Rationale: To determine the breakeven point where Truck B becomes the better buy, we need to compare the total costs for both trucks. For Truck A: Total cost = $450 + (miles / 25) * $4. For Truck B: Total cost = $650 + (miles / 35) * $4. To find the point where Truck B is the better buy, set the two total cost equations equal to each other and solve for miles. By solving this equation, we find that Sally must drive 4375 miles for Truck B to be the better buy. Choice A (500) is too low, Choice B (7500) is too high, and Choice C (1750) does not represent the breakeven point where Truck B becomes more cost-effective.

Correct Answer: B

Rationale: The square root of 1296 is 36 because 36 multiplied by 36 equals 1296. Therefore, the correct answer is 36. Choices A, C, and D are incorrect. A (24) is not the square root of 1296 because 24 multiplied by 24 is 576, not 1296. C (31) is also incorrect as 31 multiplied by 31 is 961, not 1296. D (12) is not the square root of 1296 as 12 multiplied by 12 equals 144, not 1296.

Correct Answer: D

Rationale: To determine the percentage of rainfall received during the month of October, we must first calculate the total rainfall for October and the total rainfall for the entire timeframe. Given that the total rainfall for October is 18.9 inches and the total rainfall from January to November is 106.3 inches, we can proceed with the calculation. The percentage is calculated as (18.9/106.3) x 100 = 17.7%. Therefore, the correct answer is D, 17.7%. Choice A (13.50%), Choice B (15.10%), and Choice C (16.90%) are incorrect as they do not align with the accurate calculation based on the provided data.

Correct Answer: C

Rationale: When reducing a figure by a scale factor, each dimension is multiplied by the same scale factor. In this case, the scale factor is not provided in the question. To find the scale factor, you would divide the new lengths of the sides by the original lengths. The scaled-down triangle's dimensions are the original dimensions multiplied by the scale factor. By performing the calculations, the dimensions of the dilated triangle are 6.75 cm, 3 cm, and 5.25 cm, which matches choice C. Choices A, B, and D have incorrect dimensions as they do not result from the correct application of the scale factor to the original triangle's dimensions.

Correct Answer: C

Rationale: The circumference of a circle is given by the formula Circumference = 2 x π x radius. Given that the radius of the picture frame is 3 inches, the estimated circumference can be calculated as 2 x π x 3 = 18.84 inches, which is closest to 18 inches among the given options. Choice A (12 inches) is too small, choice B (16 inches) is also underestimated, and choice D (24 inches) is too large based on the calculated value using the formula.