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How many working days in year 1901?

Here is the detail of the calculation:

Because 1901 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 5 public holidays that do not fall during a weekend and we obtain 256 working days in 1901.

Here is the list of these 5 public holidays:

1. Pesach : четверг, 4 апрель, 1901
2. Shvi'i shel Pesach : среда, 10 апрель, 1901
3. Yom Ha-Atzmaut : среда, 24 апрель, 1901
4. Rosh Hashanah : воскресенье, 15 сентябрь, 1901
5. Yom Kippur : понедельник, 23 сентябрь, 1901

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

1. Shavuot : пятница, 24 май, 1901
2. Rosh Hashanah : суббота, 14 сентябрь, 1901
3. Sukkot : суббота, 28 сентябрь, 1901
4. Shemini Atzeret / Simchat Torah : суббота, 5 октябрь, 1901