((24 * 250 + 18 * 350) / 60 * 400 + (44 * 4500 + 108 * 1500) / 20) / 400 = 250
24 * 250 = 6000
18 * 350 = 6300
6000 + 6300 = 12300
12300 / 60 = 205
205 * 400 = 82000
44 * 4500 = 198000
108 * 1500 = 162000
198000 + 162000 = 360000
360000 / 20 = 18000
82000 + 18000 = 100000
100000 / 400 = 250