2.1.12 Celsius to Fahrenheit Conversions

These types of problems used to always be on the Number Sense tests in the early 1990’s but have since been noticeably absent until recently. Here are the conversion factors:

Fahrenheit → Celsius: $C = \frac{5}{9}(F - 32)$

Celsius → Fahrenheit: $F = \frac{9}{5}C + 32$

Shortened Trick for Celsius to Fahrenheit

1. Double the given temperature in Celsius
2. Move the decimal over to the left one and subtract that from the doubled number
3. Add 32 to that result to get the answer

Example: Convert 20°C to Fahrenheit: $20°C \Rightarrow 40 - 4 = 36 \Rightarrow 36 + 32 = 68°F$

Important Values to Memorize

• 32°F = 0°C
• 212°F = 100°C
• −40°F = −40°C

Problem Set 2.1.12