Answer : The approximate relation Celsius = 1/2 Fahrenheit is a better approximation at higher temperatures
Explanation :
The formula for Celsius to Fahrenheit conversion is
![C = (F-32) \times \frac{5}{9}](https://tex.z-dn.net/?f=C%20%3D%20%28F-32%29%20%5Ctimes%20%5Cfrac%7B5%7D%7B9%7D)
At lower temperature the value that needs to be subtracted (32) is large enough as a result the approximation "celsius = 1/2 fahrenheit " does not seem valid.
For example, 50 F is 10°C.
![(50 - 32) \times \frac{5}{9} = 10 C](https://tex.z-dn.net/?f=%2850%20-%2032%29%20%5Ctimes%20%5Cfrac%7B5%7D%7B9%7D%20%3D%2010%20C)
This is almost 1/5 of Fahrenheit temperature.
But at higher temperatures , the value becomes insignificant and also the ratio 5/9 tend to be equal to 0.5.
For example, 2000 F is 1093°C
![(2000 - 32) \times \frac{5}{9} = 1093 C](https://tex.z-dn.net/?f=%282000%20-%2032%29%20%5Ctimes%20%5Cfrac%7B5%7D%7B9%7D%20%3D%201093%20C)
This is almost half of Fahrenheit temperature.
Therefore , the approximate relation Celsius = 1/2 Fahrenheit is a better approximation at higher temperatures