Bam is trying way too hard. Also, what does "fictive" mean? It means "imaginative" and doesn't apply here.
The two typing rates are not only proportional, they are equal: 52.5 words per minute (not 50.25). This is a proportion of 1.
Between two different typing rates, they are ALL proportional!
For example, if I type 20 words per minute and my friend types 200 words per minute (wpm), the proportion is 10.
If I type 58 wpm and my friend types 62 wpm, the rates are close but not equal. The proportion in this case is 31/29.
Etc. for ANY two non-zero wpm rates.