The Fahrenheit to Celsius conversion factor 5/9, comes after dividing 100 by 180. That is the range between the ice point in the Celsius and Fahrenheit scale. A simpler way of calculating this is as follows: We know that 9/5 = 1.8 = (2.0 - 0.2) = 2(1 - 0.1). This means that if you have to convert degree Celsius to Fahrenheit then you need to double the given ºC value, subtract 10%, and add 32 to it. Let's understand this by an example
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