Each bag of pears weighs 1 kg 280 gram. If the total weight of a sack containing the bag of pears is 21.76 kg, then how many bags there are in the sack?

If 260362 passengers travel everyday through Ho Chi Minh City airport, 864894 passengers travel through Hai Phong airport, 670102 passengers travel through Ha Noi airport, and 411166 passengers travel through airport. How many passengers in total travel through these four cities everyday?