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How many working days in year 2121?

Here is the detail of the calculation:

Because 2121 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 2121.

Here is the list of these 5 public holidays:

1. Pesach : четверг, 3 апрель, 2121
2. Shvi'i shel Pesach : среда, 9 апрель, 2121
3. Yom Ha-Atzmaut : среда, 23 апрель, 2121
4. Rosh Hashanah : воскресенье, 14 сентябрь, 2121
5. Yom Kippur : понедельник, 22 сентябрь, 2121

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

1. Shavuot : пятница, 23 май, 2121
2. Rosh Hashanah : суббота, 13 сентябрь, 2121
3. Sukkot : суббота, 27 сентябрь, 2121
4. Shemini Atzeret / Simchat Torah : суббота, 4 октябрь, 2121