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How many working days in year 1912?

Here is the detail of the calculation:

Because 1912 is a leap year, it has 366 days.

Let's remove 52 saturdays and 52 sundays. It remains 262 days.

Now, let's remove 7 public holidays that do not fall during a weekend and we obtain 255 working days in 1912.

Here is the list of these 7 public holidays:

1. Pesach : вторник, 2 апрель, 1912
2. Shvi'i shel Pesach : понедельник, 8 апрель, 1912
3. Yom Ha-Atzmaut : понедельник, 22 апрель, 1912
4. Shavuot : среда, 22 май, 1912
5. Rosh Hashanah : четверг, 12 сентябрь, 1912
6. Sukkot : четверг, 26 сентябрь, 1912
7. Shemini Atzeret / Simchat Torah : четверг, 3 октябрь, 1912

And here are the 2 public holidays falling on a weekend:

1. Rosh Hashanah : пятница, 13 сентябрь, 1912
2. Yom Kippur : суббота, 21 сентябрь, 1912