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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 9 public holidays that do not fall during a weekend and we obtain 252 working days in 1970.

Here is the list of these 9 public holidays:

1. New Year's Day : четверг, 1 январь, 1970
2. Independence Day : вторник, 24 февраль, 1970
3. Good Friday : пятница, 27 март, 1970
4. Spring Day : пятница, 1 май, 1970
5. Victory Day : вторник, 23 июнь, 1970
6. Midsummer Day : среда, 24 июнь, 1970
7. Independence Restoration Day : четверг, 20 август, 1970
8. Christmas Eve : четверг, 24 декабрь, 1970
9. Christmas Day : пятница, 25 декабрь, 1970

And here are the 3 public holidays falling on a weekend:

1. Easter : воскресенье, 29 март, 1970
2. Pentecost : воскресенье, 17 май, 1970
3. Second Day of Christmas : суббота, 26 декабрь, 1970