Amaze your friends! Astound your neighbors! Confuse your enemies! Calculate the day of the week for any date, all without consulting a paper OR electronic calendar!
Several years ago my dad, a brilliant man, told me about a calendar trick he used. The trick allowed him to figure the day of the week for nearly any date. While other people were still looking in their paper planners (back in the old days,) he already knew.
In 2013, Thursday is the MAGIC DAY, a reference day around which the calendar trick revolves.
March 14 (Pi Day!) is a magic day on the calendar. In fact, March 14 is a magic day regardless of which year it is, or which day of the week the date falls upon.
Let’s begin with the easy ones:
the 4th day of the 4th month and
the 6th day of the 6th month and
the 8th day of the 8th month and
the 10th day of the 10th month and
the 12th day of the 12th month
ALL fall on the same day of the week, the MAGIC DAY. In 2013 the Magic Day is Thursday.
Note that for the EVEN numbered months starting in April, the day and month match up.)
Besides those:
the 9th day of the 5th month and
the 5th day of the 9th month and
the 11th day of the 7th month and
the 7th day of the 11th month
ALL fall on the same day of the week, the MAGIC DAY. In 2013 the Magic Day is Thursday.
Note how 5 and 9 match up [think “9 to 5”] and 7 and 11 match up [think “7-11”].)
That leaves January through March. February and March are simple.
For February, the LAST day of the month is the Magic Day(Thursday this year), regardless of whether or not it is leap year.
For March, since the LAST day of February is the Magic Day, the 7th, 14th, 21st, and 28th of March also fall on the Magic Day. Pi Day is the Magic Day!
January is more difficult, but because the last day of February is the reference day, the last day of January is the same day EXCEPT in leap years. In leap year it is the day before the reference day. For example, in 2012, a leap year, the last day of January was Tuesday, not Wednesday. (Go ahead, check the calendar and see.)
Once you know these rules, you can move backward or forward in any month to determine the day of the week. For example, my son’s birthday is on the Magic Day, and mine is two days later. This year his birthday is Thursday, so mine must be Saturday.
The reference day progresses through the years. It becomes one day later every year, except in leap years when it advances two days. In 2011, the Magic Day was Monday, and it progressed two days to Wednesday in 2012. In 2013, it is Thursday, and in 2014, it will be Friday.
These days when so many people carry smart phones, it may not be as useful as it used to be. But I don’t have a smart phone. I have a dumb phone, and I still use these rules. Do you think you are geeky enough to remember and use these rules?
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