A town has four elementary schools - Ballyntine, Euclid, Providence, and Selwyn; each with a capacity of 400 students. The school board wants to assign students to schools so that their travel time by bus is as short as possible. The school board has divided the town into four districts - north, south, east, and west. The average bus travel time from each district to each school is shown in the following table:

	Travel Time (Min.)
District	Ballyntine	Euclid	Providence	Selwyn	Student Population
North	12	23	32	17	260
South	26	15	21	27	350
East	18	20	22	30	320
West	28	23	32	18	290

The school board wishes to determine the number of students that should be assigned from each district to each school to minimize the total student travel time.

On the average, what is the optimal travel time per student? Round your answer to the nearest whole number. For example, "1.856 minutes" should be entered as "2".