Mnemonic for the number of days in each month(rsapkf.org)
rsapkf.org
Mnemonic for the number of days in each month
https://rsapkf.org/weblog/days-months
15 comments
Yeah, this is what I do. Or used to do. I followed an interesting progression with it -- at some point, I stopped having to actually look at or touch my knuckles to do it, then after a number of years, I found that I (mostly) just have the months lengths memorized.
It's the odd numbered months 1-7, and even numbered months 8-12. July and August are the two adjacent 31-day months.
Also in case you did not know, the leap year is not on even hundreds of years, i.e. 1900 was not a leap year, and neither will 2100 be under the current calendar.
The exception is every four hundred years, which means 2000 was a leap year, as would 1600 have been, and 2400 will be.
This means the year is on average 365.2425 days long[1] -- a constant that I've found surprisingly useful to memorise.
[1]: Because 365 + 1/4 - 1/100 + 1/400.
The exception is every four hundred years, which means 2000 was a leap year, as would 1600 have been, and 2400 will be.
This means the year is on average 365.2425 days long[1] -- a constant that I've found surprisingly useful to memorise.
[1]: Because 365 + 1/4 - 1/100 + 1/400.
> as would 1600 have been
Though the Gregorian calendar wasn't adopted in England and America * until 1752, so no 100s or 1000s under the old calendar.
* And probably a lot of other places
Though the Gregorian calendar wasn't adopted in England and America * until 1752, so no 100s or 1000s under the old calendar.
* And probably a lot of other places
The number of days in a month sits in a nice space of complexity for me - it's hard enough to be non-trivial, but simple enough you feel you should know it.
Probably the easiest thing to remember is that short and long months generally alternate (the exceptions are December/January, and July/August).
I like the 'use the knuckles of your hands' technique - put your hands next to each other, and count the months using your knuckles and the spaces - so January (knuckle - high so long-month), February (space - low so short-month), March (knuckle - high so long-month). When you reach July, you get your left-and-right knuckles next to each other, so two long months in a row. [EDIT: I can now see that I'm about the fifth person to mention this!]
Probably the easiest thing to remember is that short and long months generally alternate (the exceptions are December/January, and July/August).
I like the 'use the knuckles of your hands' technique - put your hands next to each other, and count the months using your knuckles and the spaces - so January (knuckle - high so long-month), February (space - low so short-month), March (knuckle - high so long-month). When you reach July, you get your left-and-right knuckles next to each other, so two long months in a row. [EDIT: I can now see that I'm about the fifth person to mention this!]
Back in primary school the knuckle method that we were taught seemed too complex and slow, so I made up a word instead from the 30-day months: "apjuseno".
> In numeric format, these months correspond to 4 6 9/11.
Easy to remember for Romans: IV VI IX XI (”if you write the month number with two letters that aren’t identical”). I think that worked under the Julian calendar (https://en.wikipedia.org/wiki/Julian_calendar#Table_of_month...)
Easy to remember for Romans: IV VI IX XI (”if you write the month number with two letters that aren’t identical”). I think that worked under the Julian calendar (https://en.wikipedia.org/wiki/Julian_calendar#Table_of_month...)
In Portugal (idk about other countries) we use something like:
- Use knuckles and spaces between them
- Start with left-most pinky knuckle (in
- Count across hand: knuckle (31), space (30), knuckle (31), etc.
- Jump to right hand's index finger knuckle after left index (so it's two times knuckle, when passing from left to right hand (for July and August) and continue.
February is special: 28 or 29 days
February is special: 28 or 29 days
How is this different from the knuckle mnemonic mentioned as the first thing in TFA?
My wife makes a fist and counts her knuckles and divots on her left hand:
pinky Jan 31
divot Feb (28/29)
ring March 31
divot April 30
middle May 31
divot June 30
pointer July 31
(now head back the other way)
pointer August 31
divot September 30
middle October 31
divot November 30
ring December 31
I don't know where she learned it, but it's genius.
pinky Jan 31
divot Feb (28/29)
ring March 31
divot April 30
middle May 31
divot June 30
pointer July 31
(now head back the other way)
pointer August 31
divot September 30
middle October 31
divot November 30
ring December 31
I don't know where she learned it, but it's genius.
[deleted]
I thought I was the only one who still hadn't figured this out
feb apr jun sep nov
fapjunseno
fapjunseno
[deleted]
[0] https://en.wikipedia.org/wiki/Knuckle_mnemonic