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Topic: numerical challenge
Replies: 90   Last Post: Oct 26, 2012 7:41 PM

 Messages: [ Previous | Next ]
 Spehro Pefhany Posts: 25 Registered: 1/25/05
Re: numerical challenge
Posted: Oct 24, 2012 3:55 PM

On Wed, 24 Oct 2012 18:41:33 +0000 (UTC), Willem
<willem@turtle.stack.nl> wrote:

>krw@att.bizzzzzzzzzzzz wrote:
>) I originally discounted 2s and 5s because the only 9*0 ends in zero (assumed
>) that the '9' made a difference - it doesn't). Obviously, there is also 2
>) times 5 in each decade, so there are 408 (x0) + 40 (x100) +4 (x1000) + 409
>) (2x5) = 861.
>
>I have no idea what you mean with 9*0 and why they should make a difference.
>
>Also, you still made a mistake, 861 is not the right answer.
>
>
>SaSW, Willem

I cheated and googled. Here is an easy general method, particularly
easy with a pocket calculator:-
http://www.purplemath.com/modules/factzero.htm

and I also get the correct answer from MATLAB by using:
vpa('4089!',50000)

Then copy/paste the zeros into Ultraedit and looking at the column
number of the last zero. xxx9.

Date Subject Author
10/22/12 Rich Delaney
10/22/12 Phil Hobbs
10/22/12 Rich Delaney
10/23/12 Phil Hobbs
10/23/12 G. Morgan
10/23/12 Phil Hobbs
10/23/12 Robert Macy
10/23/12 Frederick Williams
10/24/12 Robert Macy
10/23/12 G. Morgan
10/24/12 Spehro Pefhany
10/22/12 William Elliot
10/23/12 William Elliot
10/26/12 Rich Delaney
10/22/12 John Larkin
10/23/12 Jeff Liebermann
10/23/12 John Larkin
10/23/12 John Fields
10/23/12 Phil Hobbs
10/23/12 John Larkin
10/23/12 John Fields
10/23/12 John Larkin
10/23/12 John Fields
10/23/12 krw@att.bizzzzzzzzzzzz
10/23/12 John Larkin
10/23/12 krw@att.bizzzzzzzzzzzz
10/24/12 rickman
10/24/12 John Larkin
10/24/12 P E Schoen
10/24/12 John Fields
10/23/12 YD
10/23/12 John Larkin
10/23/12 Jamie
10/23/12 krw@att.bizzzzzzzzzzzz
10/23/12 Sylvia Else
10/24/12 krw@att.bizzzzzzzzzzzz
10/24/12 Sylvia Else
10/24/12 Robert Baer
10/25/12 krw@att.bizzzzzzzzzzzz
10/24/12 Roberto Waltman
10/24/12 Spehro Pefhany
10/24/12 tm
10/24/12 John Larkin
10/24/12 John Larkin
10/24/12 Roberto Waltman
10/24/12 Spehro Pefhany
10/24/12 Roberto Waltman
10/24/12 John Larkin
10/24/12 Jamie
10/24/12 John Larkin
10/24/12 tm
10/24/12 John Larkin
10/24/12 Jamie
10/24/12 krw@att.bizzzzzzzzzzzz
10/24/12 tm
10/24/12 John Larkin
10/24/12 krw@att.bizzzzzzzzzzzz
10/24/12 krw@att.bizzzzzzzzzzzz
10/24/12 Jeff Liebermann
10/23/12 Les Cargill
10/23/12 P E Schoen
10/23/12 Nico Coesel
10/23/12 Sylvia Else
10/23/12 Nico Coesel
10/25/12 Rich Delaney
10/23/12 G. Morgan
10/23/12 Tim Williams
10/23/12 Sylvia Else
10/23/12 Sylvia Else
10/23/12 Robert Baer
10/24/12 William Elliot
10/24/12 Butch Malahide
10/24/12 William Elliot
10/24/12 Robert Baer
10/24/12 Robert Baer
10/24/12 krw@att.bizzzzzzzzzzzz
10/24/12 Butch Malahide
10/24/12 krw@att.bizzzzzzzzzzzz
10/24/12 Willem
10/24/12 Spehro Pefhany
10/24/12 krw@att.bizzzzzzzzzzzz
10/24/12 Uwe Hercksen
10/24/12 Sylvia Else
10/26/12 Rich Delaney
10/23/12 quasi
10/23/12 Robert Macy
10/23/12 John S
10/23/12 ehsjr
10/23/12 Sylvia Else
10/23/12 Mike Terry
10/23/12 Sylvia Else