Correct Answer: A

Rationale: A six-sided die has three odd numbers (1, 3, 5) out of six possible outcomes. To calculate the probability, divide the number of favorable outcomes (odd numbers) by the total number of outcomes: 3/6 = 0.5 or 50%. Therefore, the probability of rolling an odd number on a six-sided die is 50%. Choice A is correct. Choice B (66.70%) is incorrect as it does not represent the correct probability of rolling an odd number on a six-sided die. Choice C (33.30%) is incorrect as it represents the probability of rolling an even number. Choice D (25%) is incorrect as it does not reflect the correct probability of rolling an odd number on a six-sided die.

Correct Answer: D

Rationale: To express the repeating decimal 0.7777... as a fraction, let x = 0.7777... Multiplying both sides by 10 to shift the decimal point to the right gives: 10x = 7.7777... Subtracting the original equation from the new equation eliminates the repeating decimal: 10x - x = 7.7777... - 0.7777... 9x = 7 x = 7/9. Therefore, the decimal 0.7777... can be expressed as the fraction 7/9. Choices A, B, and C are incorrect as they do not accurately represent the decimal 0.7777... when converted to a fraction.

Correct Answer: A

Rationale: Subtract the fractions first: 2 5\8 - 7\8 = 1 & 5\8.

Correct Answer: B

Rationale: To convert 98.6 degrees Fahrenheit to Celsius, you can use the formula (98.6 - 32) 5/9. By solving this equation, the temperature is calculated to be 37°C. Therefore, the correct answer is B, 37 Celsius. Choice A, 35 Celsius, is incorrect because it is not the outcome of the conversion formula. Choice C, 38 Celsius, is incorrect as well, as it does not match the correct conversion result. Choice D, 36.5 Celsius, is also incorrect as it does not correspond to the accurate conversion from 98.6 degrees Fahrenheit.

Correct Answer: A

Rationale: To subtract mixed numbers, find a common denominator. Converting 6 1/2 to 6 3/6 and 2 2/3 to 2 4/6, the calculation becomes 6 3/6 - 2 4/6 = 4 1/6. Therefore, the correct answer is A. Choice B (3 1/3) is incorrect as the correct result is not an improper fraction. Choice C (3 5/6) is incorrect as it does not represent the result of the subtraction. Choice D (4 1/3) is incorrect as it does not match the correct calculation.