More Discussions for this daf
1. Taurus and Scorpio 2. North-South Determination 3. The Vilna Gaon's calculation
4. Rav Ada 5. Tekufos - Halachic vs Secular 6. Vernal Equinox
7. Gra on Tosfos D"H Abaya 8. Rashi's Siman 9. Rashi's inexact calculation
10. Solistice? 11. Rashi, D"H v'Ein Tekufos Tamuz.. 12. Rashi DH Mipnei She'Mafsid - Where does the 28 come from?
13. Bach on amud beis 14. Constellations 15. Akrav is in the South
DAF DISCUSSIONS - ERUVIN 56

Marc Diamond asked:

Shouldn't he say 3/5, not 4/5? 2000 / 1.4 = 1428.57...

Marc Diamond, Providence, RI

The Kollel replies:

Dear Marc,

The Maharshal (Chochmas Shlomo printed with the Maharsha) had a text written in Rashi that reads 4/5. He explains that Rashi used this number not as the exact side of the square which makes a diagonal of 2000. Rashi himself afterwards calculates 1428 and 2/5, without the added fraction, but as the amount that is "missing". It seems he is referring to the 4/5 missing from 2000 after adding 2/5 to 1428. 1428+571.2=1999.2. The Maharshal says afterwards that 1428 3/5 is sufficient as you noticed.

The Bach is just quoting Rashi as he is brought down by the Maharshal. (The Maharsha has a slightly different explanation).

At the end of the Bach it is written in brackets " and so it in the Venetzia edition". However, in the first edition of Venetzia we found no fraction at all added to 1428.

All the best,

Reuven Weiner