Quote Originally Posted by Dean Williams
...to express a developer dilution of (one part Dektol plus two parts water) in a ratio, it would be written 1:3. The second numeral of a ratio (the three in the Dektol example) is the total of parts needed for the solution. The first numeral (the 1) indicates one of the parts that make up the total...
So then a dilution of 1:1 would be a solution with one part of the
first numeral and zero parts of what ever else; the second numeral
minus the first equalling zero. "The second numeral of a ratio...is
the total of parts... .

Any wonder I'm not convinced?