4 ms·This is not an approximation. The conversion formula is: C = 5/9 * (F - 32) So GP's table is exact.by frutiger 7y agoThis is not an approximation. The conversion formula is: C = 5/9 * (F - 32) So GP's table is exact.tomger 7y agoThe article refers to C = 2 * (F - 30) as an approximationfrutiger 7y agoAh, I had mistaken your reply, and assumed it was to /u/u801e and not the linked article.