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: A

Rationale: The correct answer is $90. If he pays $270 per month in rent and saves a total of $360 per month, he puts $360 - $270 = $90 into his house savings account each month. Choice B ($270) is incorrect as this amount represents the rent paid, not the amount saved. Choices C ($730) and D ($810) are both significantly higher than the correct amount of $90, making them incorrect as they do not align with the given information in the question.

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 find the total amount spent by the roommates, you need to add up the individual amounts each roommate contributed. Anna contributed $18, Liz contributed $12, and Jane contributed $6. Adding these amounts together gives us $18 + $12 + $6 = $36. Therefore, the correct answer is $36. Option A ($34), Option B ($35), and Option D ($37) are incorrect as they do not match the correct calculation of the total amount spent by the roommates.

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.