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How many working days in year 1987?

Here is the detail of the calculation:

Because 1987 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 7 public holidays that do not fall during a weekend and we obtain 254 working days in 1987.

Here is the list of these 7 public holidays:

1. Pesach : вторник, 14 апрель, 1987
2. Shvi'i shel Pesach : понедельник, 20 апрель, 1987
3. Yom Ha-Atzmaut : понедельник, 4 май, 1987
4. Shavuot : среда, 3 июнь, 1987
5. Rosh Hashanah : четверг, 24 сентябрь, 1987
6. Sukkot : четверг, 8 октябрь, 1987
7. Shemini Atzeret / Simchat Torah : четверг, 15 октябрь, 1987

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

1. Rosh Hashanah : пятница, 25 сентябрь, 1987
2. Yom Kippur : суббота, 3 октябрь, 1987