Which equation converts Celsius to Fahrenheit?

Which equation converts Celsius to Fahrenheit?

• A. F = 9/5 C + 32.
• B. F = C + 273.
• C. F = C x 2.
• D. F = 5/9 (C - 32).

Answer: (A)

Converting Celsius to Fahrenheit requires scaling the temperature by the same degree size and then shifting the zero point to match Fahrenheit. The correct formula is F = (9/5) × C + 32. It works because Fahrenheit and Celsius step by the same amount per degree, but water’s freezing point is 0°C and 32°F, so you add 32 after the scaling. For example, 0°C becomes 32°F, and 100°C becomes 212°F, which aligns with the known boiling point of water in Fahrenheit. The other forms don’t fit: adding 273 would convert to Kelvin, doubling Celsius isn’t a true conversion, and the inverse form would be C = (5/9)(F − 32), not F = (5/9)(C − 32).

Converting Celsius to Fahrenheit requires scaling the temperature by the same degree size and then shifting the zero point to match Fahrenheit. The correct formula is F = (9/5) × C + 32. It works because Fahrenheit and Celsius step by the same amount per degree, but water’s freezing point is 0°C and 32°F, so you add 32 after the scaling. For example, 0°C becomes 32°F, and 100°C becomes 212°F, which aligns with the known boiling point of water in Fahrenheit. The other forms don’t fit: adding 273 would convert to Kelvin, doubling Celsius isn’t a true conversion, and the inverse form would be C = (5/9)(F − 32), not F = (5/9)(C − 32).