If the temperature is 100 degrees Fahrenheit, what is the temperature to the nearest degree, Centigrade?

To find the equivalent temperature on the Centigrade (or Celsius) scale, you must first account for the different reference points for freezing. The Fahrenheit scale sets the freezing point of water at 32 degrees, while the Celsius scale sets it at 0. So, the first step is to subtract 32 from the Fahrenheit temperature: 100 - 32 = 68. The next step adjusts for the fact that the degrees themselves are different sizes. A Celsius degree is a larger unit of heat than a Fahrenheit degree. We multiply the result by the fraction 5/9, which gives us 37.77... Rounding this to the nearest degree gives us 38.

The two temperature scales were developed around the same time in the early 18th century. German physicist Daniel Gabriel Fahrenheit created his scale first, using the temperature of a freezing brine solution for his zero point. A few decades later, Swedish astronomer Anders Celsius proposed a simpler system based on the properties of water, with 0 for freezing and 100 for boiling. This logical, decimal-based scale was much easier for scientists to work with and was eventually adopted by most of the world.

Interestingly, Celsius originally designed his scale upside down, with 100 for freezing and 0 for boiling. The scale was inverted to its familiar form after his death. Today, the United States, along with a few other territories, remains one of the last holdouts to primarily use the Fahrenheit system for everyday temperature measurement, while the rest of the world and the entire scientific community rely on Celsius.