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HOW TO FIND THE DAY OF YOUR BIRTH-DATE?

     


     The great German mathematician Karl Fredrich Gauss devised a beautifully simple formula in 1800 to calculate the day of the week corresponding to any date.

   N = D +E+F+G+(G/4)
 Day of week = N mod 7.

     Let us understand the formula with an example.  I want to find the day for the date "15 September 1959".

Step 1. D = Day of the month - Here it is '15'

        2. E = a number allotted by Friedrich for each month
               Month               E
                 Jan 1                0
                 Feb 2               3
                 Mar 3              2
                 Apr  4              5
                 May 5              0
                 June 6              3
                 July   7             5
                 Aug 8               1
                 Sep 9                4
                 Oct 10              6
                 Nov 11             2
                 Dec 12             4
    in our case E = 4

3. Next F : Divide the century by 4 , if reminders are 0,1,2,3, Then
              F = 0,5,3,1 respectively
     our case : 19/4 reminder is 3, so F=1

4. G: Last two digits of the year =59

5. (G/4) tells: divide G by 4 and take only whole number of the answer. Hence 59/4=14.

     Now putting everything together in the formula , N= D+E+F+G+(G/4)
 6. N= 15 +4+1+59+14 =93
     Day = 93 Mod 7
     That is divide 93 by 7 and take the reminder it is 2
      second day of week.  It is Tuesday!
        Got it finally

     Also cross-checked using the website "Timeanddate.com".(May be, this is algorithm used in the site also).  You can find out day of the next new year.  Hope, it does not fall on a Sunday.
     Let us appreciate the genius Karl Friedrich.      
                            ------------------------------------------   

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