3. A certain number of boys and girls went camping during the summer break. They planned an ecological action that they would finish in 29 days if each child worked evenly - working the same part of the job in any given days. The boys worked a bit faster; in the same time, 2 boys do as much work as 3 girls. Fortunately, after three days of starting the work, a larger group of children joined them: boys - 8 times more than the initial number of girls, and girls - 18 times more than the initial number of boys. The newly arrived children worked with the same dynamics as the initially arrived ones. How many days in total were working days?