I don't know if there is a limit on the length of the thread. My posts don't seem to go in any more to:
http://www.jiskha.com/display.cgi?id=1253908539
The correct formulas are:
F = C*9/5 + 32
C = (F-32)*5/9
The graduations are wider apart on the C scale, that is why the factor 9/5 when converting to F.