What precent of the southern population must take an oath of loyalty to be able to be represented in congress why did you choose that number?

To be represented in Congress, 10% of the voters in a Southern state were required to take an oath of loyalty under the Reconstruction era's Wade-Davis Bill. This number was chosen as a compromise to ensure that a significant portion of the population had demonstrated loyalty to the Union, while not being so high as to exclude a majority of potential voters. This threshold aimed to facilitate the reintegration of Southern states while promoting loyalty to the Union.