The Oxford Dictionary defines equity as fairness, or justice.
Equity means treating students fairly.
Fair treatment however is not necessarily equal treatment. For example it may be equal treatment to require students to travel to China to complete a unit but it is not fair treatment. Some students may easily comply with this requirement while others cannot comply. Although the treatment is equal, the effect is discriminatory. Just as it would not be appropriate to build more Universities to address equity issues confronting the socioeconomically disadvantaged students so to it would not be appropriate to address the geographic isolation of students by simply providing more units in the external mode.