What does 100 f mean in c?

Answer 1

The conversion formula for Fahrenheit to Celsius (or centigrade) is (°F- 32) x 5/9 = °C.

So (100˚-32=68˚) times 5/9 (68/9= about 7.5) times 5 = 37.5˚ (using a calculator it came to 37.777+˚c)

When converting mentally, where accuracy is not essential, I subtract the 32 from the original ˚ and then divide by 2 and add 1/10th. It gives a rough but adequate range.