91/Historical Note

Historical Note on $91$ (Ninety-One)

There are $91$ days in a quarter-year: $13$ weeks of $7$ days each.


Sources

  • 1986: David Wells: Curious and Interesting Numbers ... (previous) ... (next): $91$
  • 1997: David Wells: Curious and Interesting Numbers (2nd ed.) ... (previous) ... (next): $91$
This article is issued from ProofWiki. The text is available under Creative Commons Attribution-ShareAlike License unless otherwise noted. Additional terms may apply for the media files.