0 being the coldest day measured and 100 the hottest.
(As tested by other means)
It’s a scale based on human perception and works with whole numbers, still.
A fever of 100 vs 101 as opposed to a fever of 37.78 vs 38.3. (No, these are not fever thresholds, I’m using whole numbers as an example. Yes Fahrenheit also uses decimals. My point is graduation of measure)
Metric & SI units may be better but you’re still wrong.