The 'rooster' to hen ratio of 1:10 that is often cited is primarily for fertility efficiency in commercial breeding facilities.You can only have one roo per 10 hens if you are going to keep them all make sure they all have the right amount of hens
It doesn't mean that if a cockbird has 10 hens that he won't abuse or over mate them.
Many breeders keep pairs, trios, quads, etc ....short term and/or long term.
It all depends on the temperaments of the cock and hens and sometimes housing provided.
Backyard flocks can achieve good fertility with a larger ratio.