How many working days in year 1926?
Here is the detail of the calculation:
Because 1926 is not a leap year, it has 365 days.
Let's remove 52 saturdays and 52 sundays. It remains 261 days.
Now, let's remove 3 public holidays that do not fall during a weekend and we obtain 258 working days in 1926.
 Here is the list of these 3 public holidays: 
 
 1. New Year's Day : пятница, 1 январь, 1926 
2. Good Friday : пятница, 2 апрель, 1926 
3. National Day : понедельник, 9 август, 1926 
And here are the 2 public holidays falling on a weekend:
1. Labour Day : суббота, 1 май, 1926 
2. Christmas Day : суббота, 25 декабрь, 1926