Study the given pie charts and answer the question that follows.

The pie charts show the distribution of students of graduate and post graduate levels in five different institutes P, Q, R, S and T in a town.

(i) Total number of students of graduate level in five different institutes = 12400

(ii) Total number of students of post graduate level in five different institutes = 8000

The difference between the average number of students of graduate level in institutes P, R and T to the average of students of postgraduate level in institutes P, R and T is: