quota for sorority

Hey so I will be attending Arkansas this fall and I'm rushing. I come from a school about 50 minutes from Fayetteville and a lot of girls at my school are going to Arkansas and are rushing (every year my school sends a bunch of people to Fayetville)... anyway, I am a legacy of a certain sorority and a girl that I know from school (going to be a sophomore at Arkansas next year) that is in the sorority that I'm a legacy to, told a mom (who then told my mom) that this fall their quota only allows them to take 3 girls from my school. First of all I know just cause I'm a legacy I'm not guaranteed one of these spots, nor do I know if ill even like the house but.. I'm just curious, do sororities really stick to these "only certain number of girls from this school", stuff like that?