This video tutorial is in the Education category which will show you how to convert Fahrenheit to Celsius in your head. This method is a good estimate for converting temperatures. However, do not use this for accurate temperature conversions. Let's say you want to convert 22 degree Celsius to Fahrenheit. 1st step is to double the figure, that is, add 22 plus 22 which is 44. Next add 44 with 30, which gives the result 74. So, 22degree Celsius is equal to 74 degree Fahrenheit. Similarly, 32 degree Celsius is equal to 32 + 32 + 30 = 94 degree Fahrenheit. It's that simple.