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How many working days in year 1905?

Here is the detail of the calculation:

Because 1905 is not a leap year, it has 365 days.

Let's remove 52 saturdays and 53 sundays. It remains 260 days.

Now, let's remove 9 public holidays that do not fall during a weekend and we obtain 251 working days in 1905.

Here is the list of these 9 public holidays:

1. National Day : среда, 15 март, 1905
2. Good Friday : пятница, 21 апрель, 1905
3. Easter Monday : понедельник, 24 апрель, 1905
4. Labour Day : понедельник, 1 май, 1905
5. Pentecost Monday : понедельник, 12 июнь, 1905
6. National Day : понедельник, 23 октябрь, 1905
7. All Saints' Day : среда, 1 ноябрь, 1905
8. Christmas Day : понедельник, 25 декабрь, 1905
9. Second Day of Christmas : вторник, 26 декабрь, 1905

And here are the 4 public holidays falling on a weekend:

1. New Year's Day : воскресенье, 1 январь, 1905
2. Easter Sunday : воскресенье, 23 апрель, 1905
3. Pentecost Sunday : воскресенье, 11 июнь, 1905
4. State Foundation Day : воскресенье, 20 август, 1905