Calculate What Day of the Week it is With Our Simple Formula
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Hi, we just found your website and are amazed. Just curious, how did you figure this formula out and what is this it called? Also how did you calculate the key numbers??
This is amazing thank you!
How to find the one quarter of two Digits?
One quarter or two digits = the two digits (or any number of digits) divided by 4.
1/4 * 28 = 1/4 * 28/1 = (1 * 28) / (4 * 1) = 28/4 = 7
this doesnt work for 3 of March 2147. Can anyone help?
Hi, Ana,
We’re not sure that the formula is intended for years beyond 2099. We’ve tried a few examples for years 2100 through 2199, and if one subtracts 3 instead of 1 before the last step, it works for the sample dates that we’ve tried, including March 3, 2147. But we’re not sure if it would apply to all dates in that yearly span.
Hope this helps!
Here's a method I've tested for all dates up to the year 5000. It generalizes the part of the method under the "Note" section. Instead of conditionally adding 2, 4, etc, always add a term. The term should be equal to (3 - y % 4) * 2 where y is the first two digests of the year.
Not working for August 31, 2013 or for June 3rd 1927 unless I’m doing something wrong.
August 31 2013 I got Tuesday but it is Saturday
June 3rd 1927 I got Thursday but it is Friday
Can anyone help?
Hi, Mac,
For August 31, 2013, the formula is:
13 + 3 (one quarter of 13) + 3 (the number for the month of August) + 31 (the day) = 50
Because 2013 is in that 2000 to 2099 range, though, you’ll need to subtract 1 to this sum, resulting in 49.
Then, divide 49 by 7, which yields no remainder (0). A remainder of 0 means that it is a Saturday.
For June 3, 1927, the formula is:
27 + 6 (one quarter of 27) + 5 (the number for the month of June) + 3 (the day) = 41
Because 1927 is between 1900 and 1999, you do not add or subtract anything at this stage.
Then, divide 41 by 7, which yields a remainder of 6 via long division. [Note that when using a calculator, you get 5.857. You’d then need to multiply 0.857 by 7 to get the remainder of 5.999 (and round up to 6).] A remainder of 6 means that it is a Friday.
Hope this helps!
this doesn't seem to work for February 4, 2000.
00
+0
=0
+4
=4
+3
=7
-1
=6
/7
= no remainder
= Saturday
But, the real answer is Friday..?
You can't divide 6 by 7 so therefore 6 is the remainder 6 would be a Friday.