What is the formula to convert Fahrenheit to ...

The easy way is to take the temperature in Fahrenheit, subtract 32, and divide by 1.8.

F-32=(x/9)*5=C

To put the answer in a different way ...

C = (F - 32) / 1.8

For example, how many degrees C is 77 degrees F? ...

C = (77 - 32) / 1.8

C = 45 / 1.8

C = 25

i recommend using one of the many converters on the web - http://www.wbuf.noaa.gov/tempfc.htm

http://www.calculator.com/

http://www.convert-me.com/en/

http://www.onlineconversion.com/

good luck

to get a basically close approximation, much like the current answer i see here but skipping the decimal part;  subtract 32 and divide by 2 . you will be very close. if you must be precise, or at least more precise  search for free conversion software on line. they often do much more metric conversion.  inches to centimetres, miles to kilmeters etc. always choose a respected download site. lots of nasty stuff out there.