Correct Answer: B

Rationale: Find a common denominator to subtract: 17 2\3 - 8 5\9 = 9 1\9.

Correct Answer: A

Rationale: To divide mixed numbers, convert them to improper fractions and then multiply by the reciprocal of the divisor. Here, 4 7/8 = 39/8 and 1 1/6 = 7/6. Dividing 39/8 by 7/6 gives 39/8 · 7/6 = 39/8 * 6/7 = 234/56 = 4 5/28. Therefore, the correct answer is A. Choices B, C, and D are incorrect as they do not represent the correct result of dividing 4 7/8 by 1 1/6.

Correct Answer: B

Rationale: To find 80% of a number, you multiply the number by 0.8. Therefore, 80% of 55 is calculated as 0.8 55 = 44. Choice A (40), choice C (39), and choice D (45) are incorrect as they do not represent the correct calculation for 80% of 55.

Correct Answer: A

Rationale: To subtract mixed numbers, first subtract the fractions: 1/8 - 1/2 = -3/8. Then, subtract the whole numbers: 12 - 9 = 3. Combine the whole number and fraction: 3 - 3/8 = 2 5/8. Therefore, the correct answer is A. Choice B is incorrect because it does not reflect the correct subtraction of the fractions. Choices C and D are incorrect as they do not result from the correct subtraction process outlined above.

Correct Answer: B

Rationale: To find the sum of 1/3, 1/4, and 1/6, we need to first find a common denominator. The least common multiple of 3, 4, and 6 is 12. So, we rewrite the fractions with the common denominator: 1/3 = 4/12, 1/4 = 3/12, and 1/6 = 2/12. Adding these fractions together gives us 4/12 + 3/12 + 2/12 = 9/12, which simplifies to 3/4 or 1/2. Therefore, the correct answer is 1/2. Choice A (5/12) is incorrect because it does not represent the sum of the fractions given. Choices C (1/3) and D (1/4) are also incorrect as they are individual fractions and do not represent the sum of the fractions provided.