There is no "typical" ratio of soldiers that would be consistent across all premodern armies. Different societies will have different cultural and technological influences on their military organization, as well as the practical considerations of what the purpose of military action might be for any given campaign. In addition, these concepts of unit "types" is often more of a scholarly imposition than a reflection of how contemporary people might have actually thought about their military organization. An "archer" might be exclusively relied on as a foot skirmisher. They might also play a role as light infantry or as mounted soldiers. "Cavalry" might dismount and fight on foot according to the tactical situation or the order of their commander. Is a pikeman who abandons his 18-foot weapon so that he can fight more easily in a siege or assault an entrenched position no longer a pikeman? Premodern armies were not as bureaucratized as modern forces are and generally did not have the same capacity for strict categorization, explicit doctrines, and rigorously centralized control over military organization as we do today.