Why is the formula 'degrees Fahrenheit equals 1.8 times degrees celsius plus 32'?

Answer 1

Fahrenheit is a temperature scale named after Daniel Gabriel Fahrenheit (1686-1736), a German physicist who proposed it in 1724. On this scale, the freezing point of water is 32 degrees Fahrenheit (°F) and the boiling point 212 °F (at standard atmospheric pressure), placing the boiling and freezing points of water exactly 180 degrees apart. A degree on the Fahrenheit scale is 1/180th part of interval between the ice point and the steam point or the boiling point. On the Celsius scale, the freezing and boiling points of water are 100 degrees apart, hence the unit of this scale. A temperature interval of one degree Fahrenheit is an interval of 5⁄9 of a degree Celsius. The Fahrenheit and Celsius scales coincide at −40 degrees (i.e. −40 °F and −40 °C describe the same temperature).

Answer 2

The conversion from Fahrenheit to Celsius changes the size of the measured "degrees", which are larger in Celsius. But the starting points are also different : Celsius establishes the freezing point of water at 0° C, but Fahrenheit defines this point as 32° F, so the 32 is added to Fahrenheit as a constant.

F = 9/5 C + 32 or F = 1.8 C +32

means Fahrenheit temperature = (9/5 x Celsius temperature)+ 32