Loading ...
Sorry, an error occurred while loading the content.
 

Re: [Mental Calculation] prime factors

Expand Messages
  • Frank Chin
    By using Microsoft Excel, I found that:- 10001 = 73 x 137 9999 = 101 x 99   Therefore followed what had been discussed by Andie on 1001 & 999, we can use
    Message 1 of 7 , Jul 31, 2008
      By using Microsoft Excel, I found that:-
      10001 = 73 x 137
      9999 = 101 x 99
       
      Therefore followed what had been discussed by Andie on 1001 & 999, we can use alternate addition and subtraction of four digits group to determine the prime factors of 73 and 137. (only when else fail and you are stucked) We can also use addition of four digits group to determine prime factor of 101 and factor of 99. Of course we can use alternate addition and subtraction of two digits to determine prime factor of 101.
       
      For 10001, e.g. for number 197389737, 9737-9738 + 1 = 0, therefore 197389737 is evenly divisible by 73 and 137.
      For 9999, e.g. for number 129137085, 7085+2913+1= 9999, therefore 129137085 is evenly divisible by 101 and 99 (9 x 11).
      For 101, e.g. for number 9336642, 42-66+33-9=0, therefore 9336642 is evenly divisible by 101.
       
      Just my thought on the subject.
      Regards
      Frank Chin


      __________________________________________________________
      Not happy with your email address?.
      Get the one you really want - millions of new email addresses available now at Yahoo! http://uk.docs.yahoo.com/ymail/new.html

      [Non-text portions of this message have been removed]
    Your message has been successfully submitted and would be delivered to recipients shortly.