But is the goal to hire from certain schools or to hire certain races?
The axiom presented is that the employee composition must mirror the surrounding social composition, ergo you are hiring for racial reasons because you must set quotas and then hire based upon satisfying (and not exceeding) those quotas.
As an example, if the social composition is composed of 40% Earthlings, 30% Martians, 20% Venusians, and 10% Mercurians and your workforce consists of 10 men: You cannot ever hire more than 4 Earthlings or 3 Martians or 2 Venusians or 1 Mercurian and must refuse or terminate any excess. If you cannot hire even 1 Mercurian at all you arguably can't hire anyone.
That's racist.