F
9
5
C
32
=
+
One way to remember when to use 9/5 and when to
use 5/9 is to keep in mind that the Fahrenheit scale has
more divisions than the Celsius scale. In going from
Celsius to Fahrenheit, multiply by the ratio that is
larger; in going from Fahrenheit to Celsius, use the
smaller ratio.
Another method of converting temperatures from
one scale to another is the decimal method. This
method uses the ratio 1°C equals 1.8°F. To find
Fahrenheit from Celsius, multiply the Celsius value by
1.8 and add 32. To find Celsius from Fahrenheit,
1-14
1Fahrenheit temperatures are rounded to the nearest 0.5 degree. For a more exact conversion, utilize the
psychrometric computer or the mathematical method.
Table1-2
Table 1-2.—Temperature Conversion Scale
