Network design problem using Excel Solver (USE Simplex LP in the solver)

Maryville has built a new elementary school so that the town now has a total of four schoolsAddison, Beeks, Canfield, and Daley. Each has a capacity of 400 students. The city wants to assign children to schools so that their travel time by bus is as short as possible. It has partitioned the town into five districts conforming to population densitynorth, south, east, west, and central. The average bus travel time from each district to each school is shown as follows:

How many children will be assigned from the North District to Addison school?

Please help me out! Will upvote

TRAVEL TIME (MIN) DISTRICT ADDISON BEEKS CANFIELD DALEY STUDENT POPULATION North 12 23 35 17 270 South 26 15 21 27 310 East 18 20 22 31 320 West 29 24 35 10 220 Central 15 10 23 16 280 6 A B D E F G H 1 J K L M N Area Beeks Addison Canfield Daley District North South East West Central School capacity Students assigned Student Students population assigned 270 310 320 220 280 Time = mins Bus Travel Time (mins): 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 District North South East West Central Addison 12 26 18 29 15 Area Beeks 23 15 20 24 10 Canfield 35 21 22 35 23 Daley 17 27 31 10 16