In 2005, a travel agency organized a tour to Foz do Iguaçu, distributing the people in buses with 27 seats, and it was necessary to form an incomplete bus with 19 seats. In 2006, the number of participants increased by 53, and they continued to use buses with 27 seats. How many more buses were needed and how many people were in the incomplete bus in 2006?
We have a bus with $27-19=8$ free seats and still need to accommodate $53-8=45$ participants in buses with 27 seats. It is clear that one bus is not enough, so we need 2 buses and there will be $2 \times 27-45=9$ free seats in the last bus. 18 people remained in the incomplete bus.