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How many working days in year 1921?

Here is the detail of the calculation:

Because 1921 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 8 public holidays that do not fall during a weekend and we obtain 252 working days in 1921.

Here is the list of these 8 public holidays:

1. Purim : четверг, 24 март, 1921
2. Yom Ha-Atzmaut : четверг, 12 май, 1921
3. Shavuot : воскресенье, 12 июнь, 1921
4. Rosh Hashanah : понедельник, 3 октябрь, 1921
5. Rosh Hashanah : вторник, 4 октябрь, 1921
6. Yom Kippur : среда, 12 октябрь, 1921
7. Sukkot : понедельник, 17 октябрь, 1921
8. Shemini Atzeret / Simchat Torah : понедельник, 24 октябрь, 1921

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

1. Pesach : суббота, 23 апрель, 1921
2. Shvi'i shel Pesach : пятница, 29 апрель, 1921