Wednesday, June 5, 2019

DAY FOR ANY DATE (From 1900 to 2099)


 DAY FOR ANY DATE (From 1900 to 2099)

It is always a pleasure to do something extra ordinary. Finding a day for any date is one among them. If we practice the method described in this post, we will be able to find out at a high speed. If we practice this correctly and continuously, we will be able to tell the day much before some one finds this out using a smart phone or laptop.

With a little practice, we can quickly and easily determine the day of any date. First we assign a code number to every day of the week. They are easy to remember:

Day                                        Code
Monday                             1
Tuesday                              2
Wednesday                       3
Thursday                            4
Friday                                 5
Saturday                            6
Sunday                               7 or 0
Next we assign a code for every month of the year. These month codes are used for any year, with two exceptions. In a leap year (like 2000 or 2008 or 2012, etc), the month code for January is 5, and the month code for February is 1. To make the month codes easier to remember, use the table below.

Month                  Code     How to remember
January                6*           The season is WINTER (6 letters).
February              2*           February is the 2nd month of the year.
March                  2             We march with TWO feet.
April                     5             APRIL and FOOLS have 5 letters.
May                      0             May Day is a HOLIDAY. So ZERO work.
June                     3             School will be open for the KID (3 letters for the KID)
July                       5             Let us assume JULIE (5 letters) will have birthday party in July
August                 1             August begins with A, the 1st letter of English alphabets.
September         4             End of RAIN (4 letters) in Northern states.
October              6             DASERA celebrations in Mysore. (6 letters)
November          2             11th month of the year. 1 plus 1 is 2.
December          4             We celebrate XMAS and the month is COLD (both are 4 letters)

*In a leap year, the code for January is 5 and the code for February is 1. (One less than the usual code)

Year code for the current century.
We assign a code for every year. The code for 21st century (years from 2000 to 2099) is determined as below:

Divide the last two digits of the year by 4 (ignoring any remainder) and add the quotient to the last two digits. Then reduce the initial year code by subtracting highest multiple of 7 from it.

For example, consider the current year 2019. The initial year code is 19 + 4 (19/4) = 23. Highest multiple of 7 below 23 is 21. Subtract it from 23. So the year code for 2019 is 2 (23 – 21).

Day calculation.
First, add the date, month code and year code together. Then deduct the highest multiple of seven from the sum. The remainder is the code for the day.

Now, let us find out the day of December 25th of this year.
First add the date, month code and the year code together. In our case it is 31 (25+4+2). Then subtract the highest multiple of 7 from this result. In our case it is 3 (31 – 28). This is the code for the day. And the day is Wednesday. So, Dec 25th of this year will be a Wednesday.
Note: it is very easy to remember the codes for the days and the month. For any year we can calculate the code mentally with practice. Keep practicing and you will be able to tell the day with a great speed. (We should be familiar with seventh table).

For your ready reference, the multiples of 7 are: 14, 21, 28, 35, 42, 49, 56, 63, 70, 77, 84, 91, 98, 105, 112, 119. These only will be required.

Use the same method to find out any day.

Year code for the previous century (Years from 1900 to 1999).
Use the same method as the current century. After determining the year code, add one to it. That will be final year code. For example, the initial year code for 1955 will be 55 + 13 (55/4) = 68. Highest multiple of seven is 63. So, the code is 5 (68-63). Now add one to this to get the final code for the year. Therefore, the code for 1955 is 6 (5+1).

Let us find out the day for 11.09.1955. Add the date and codes together. 11 + 4 + 6 = 21. Highest multiple of seven is 21. Deduct this from the initial code. 21 – 21 = 0. Therefore 11.09.55 was a Sunday.


If you want to extend your capabilities, use the information below.

For dates in the 1800s, add 3 to the year code.

For dates in the 2100s, add 5 to the year code.




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