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How many working days in year 1931?

Here is the detail of the calculation:

Because 1931 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 8 public holidays that do not fall during a weekend and we obtain 253 working days in 1931.

Here is the list of these 8 public holidays:

1. New Year's Day : четверг, 1 январь, 1931
2. Good Friday : пятница, 3 апрель, 1931
3. Easter Monday : понедельник, 6 апрель, 1931
4. Labour Day : пятница, 1 май, 1931
5. Pentecost Monday : понедельник, 25 май, 1931
6. State Foundation Day : четверг, 20 август, 1931
7. National Day : пятница, 23 октябрь, 1931
8. Christmas Day : пятница, 25 декабрь, 1931

And here are the 5 public holidays falling on a weekend:

1. National Day : воскресенье, 15 март, 1931
2. Easter Sunday : воскресенье, 5 апрель, 1931
3. Pentecost Sunday : воскресенье, 24 май, 1931
4. All Saints' Day : воскресенье, 1 ноябрь, 1931
5. Second Day of Christmas : суббота, 26 декабрь, 1931