cbf94194_Euclid_5_Intro_html__Definitions
[0] 5. [Brief comments] Controversy about this definition seems to begin in the 16th cent. [Definitions] 
Magnitudes are said to be in the same ratio, first to second and third to fourth, whenever equal multiples of the first and third are either together greater than or together equal to or together less than the equal multiples of the second and fourth, according to any respective multiplications,
Euclid.5.Intro.html
Definitions