facts:

government can randomly drug test students receiving financial aid (fake law)

SSU enrolls 15,000 students. Of those 15,000 students, 14,500 receive some form of state-supported financial aid. 4,000 receive ES Grants, which are reserved to low income students. SSU randomly selected 250 students to test, 232 of whom were ES Grant recipients. SSU claims this was a statistical anomaly.

How do I prove that the chances of this happening in a random test are preposterous?

Thanks for any help

Note: I am not a statistics student, this would just help me and my group prove the case that our 'client' was wronged.