This is a shitpost? Seems like a LPT as a useful, quick approximation, since the real formula is “subtract 32, divide by 9/5”. 30≈32, and 2≈9/5, as long as you’re figuring out what to wear for the day, not working in a chemistry lab. (Don’t burn your meth, fer gawdsakes!)

For 32°F, the approximation is 1°C, and even where the scales align at -40°, it works out to -35°C.