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How many working days in year 1970?

Here is the detail of the calculation:

Because 1970 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 1970.

Here is the list of these 8 public holidays:

1. Purim : воскресенье, 22 март, 1970
2. Pesach : вторник, 21 апрель, 1970
3. Shvi'i shel Pesach : понедельник, 27 апрель, 1970
4. Yom Ha-Atzmaut : понедельник, 11 май, 1970
5. Shavuot : среда, 10 июнь, 1970
6. Rosh Hashanah : четверг, 1 октябрь, 1970
7. Sukkot : четверг, 15 октябрь, 1970
8. Shemini Atzeret / Simchat Torah : четверг, 22 октябрь, 1970

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

1. Rosh Hashanah : пятница, 2 октябрь, 1970
2. Yom Kippur : суббота, 10 октябрь, 1970