15\25 + 42\52 = ?

Correct Answer: A

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.

Correct Answer: A

Rationale: To add 12 1/21 and 3 1/3, first add the whole numbers: 12 + 3 = 15. Then, add the fractions: 1/21 + 1/3. To find a common denominator, multiply 21 by 3 to get 63. Convert 1/21 to an equivalent fraction with a denominator of 63 by multiplying the numerator and denominator by 3, resulting in 3/63. Now add 3/63 (equivalent to 1/21) and 21/63 (equivalent to 1/3) to get 24/63. Simplifying 24/63 gives 8/21. Therefore, the sum is 15 8/21. Choices B, C, and D are incorrect because they do not result from the correct addition of the given numbers and fractions.

Correct Answer: A

Rationale: To determine how much board Alan needs to cut off, subtract the length of the table from the length of the board: 7 7/8 - 6 1/2 = 1 3/8. Therefore, Alan needs to cut off 1 3/8 feet from the board. Choice A is correct. Choice B (2) is incorrect because the subtraction result is 1 3/8, not 2. Choice C (7/8) is incorrect as it represents only the fraction part of the answer, not the whole amount. Choice D (3/4) is incorrect as it is a different fraction value than the result of the subtraction.

Correct Answer: A

Rationale: To convert a fraction into a ratio, you express it as a ratio of two numbers separated by a colon. Therefore, 22/91 as a ratio is 22:91. Choice B (1/3) is a different fraction not equivalent to 22/91. Choice C (22/91) is the original fraction and not the ratio form. Choice D is irrelevant to the question.

Correct Answer: A

Rationale: To find the value of x, set up the proportion 7/9 = x/63. Cross multiply to get 7*63 = 9*x. This simplifies to 441 = 9x. Divide both sides by 9 to solve for x, giving x = 49. Therefore, the correct answer is A. Choice B (x = 39), Choice C (x = 50), and Choice D (x = 59) are incorrect as they do not match the correct calculation based on the proportion set up.