DB0FHN

DK2ZA  > HUMOUR   11.03.04 19:39l 120 Lines 3227 Bytes #999 (99) @ WW
BID : HUFDD9DB0FOR
Read: DH0GHU GUEST DK2ZA DL4NWM
Subj: re: ZL3AI Math/...
Path: DB0FHN<DB0FOR
Sent: 040311/1845z @:DB0FOR.#BAY.DEU.EU [Forchheim/JN59MO] DP6.00 $:HUFDD9DB0FO
From: DK2ZA @ DB0FOR.#BAY.DEU.EU (Helmut)
To:   HUMOUR @ WW 



  ZL3AI gave us this neat little trick:


> Math
> ----
> Try This.....
> 
> Here is a math trick so unbelievable that it will stump you. Personally
> I would like to know who came up with this and why that person is not
> running the country.
> 
> 1. Grab a calculator. (you won't be able to do this one in your head)
> 2. Key in the first three digits of your phone number(NOT the area code)
> 3. Multiply by 80
> 4. Add 1
> 5. Multiply by 250
> 6. Add the last 4 digits of your phone number
> 7. Add the last 4 digits of your phone number again.
> 8. Subtract 250
> 9. Divide number by 2
> 
> Do you recognize the answer???


 If your telephone number has 7 digits that number is reproduced at
 the end. In fact it works with any 7 digit number but not with any
 other number of digits.


 Here is how this trick has been constructed:


 First we take a 7 digit number, for example  1234567.

 This can be written as  123 * 10000 + 4567

 Now if you tell anybody to take the first three digits of his telephone
 number, multiply it by 10000 and add the last four digits to obtain the
 same number again, he would probably see the trick at first glance.

 So we make it a little more complicated.

 Let's multiply the whole thing by 2 and then divide it by 2.
 This does not change anything, but makes it look more interesting!

 We now have

              ( 123 * 20000 + 4567 + 4567 ) / 2

 and its value is still 1234567.

 To make things even more difficult we disguise the number 20000
 as 80 * 250 which gives

              ( 123 * 80 * 250 + 4567 + 4567 ) / 2

 Now comes a really clever idea:

 Instead of 123 * 80 we write ( 123 * 80 + 1 ). As this is multiplied
 by 250 we now have 250 too much. So before dividing by 2 we tell our
 victim to subtract 250 which again changes nothing and gives the
 result 1234567.

            ( ( 123 * 80 + 1 ) * 250 + 4567 + 4567 - 250 ) / 2


 This is the calculation which is described in steps 1 .. 9 above.


 It is not too difficult to find variations of this general idea.


 For example: The number 2 is replaced by 3. Then we have

              ( 123 * 30000 + 4567 + 4567 + 4567 ) / 3

 Observing that 30000 = 48 * 625 this can be improved:

              ( 123 * 48 * 625 + 4567 + 4567 + 4567 ) / 3

 Now comes the above mentioned clever idea:

              ( ( 123 * 48 + 1 ) * 625 + 4567 + 4567 + 4567 - 625 ) / 3


 The recipe would now look like this:

   
   1. Grab a calculator. (you won't be able to do this one in your head)
   2. Key in the first three digits of your 7 digit phone number
   3. Multiply by 48
   4. Add 1
   5. Multiply by 625
   6. Add the last 4 digits of your phone number
   7. Add the last 4 digits of your phone number again.
   8. Add the last 4 digits of your phone number one more time.
   9. Subtract 625
  10. Divide number by 3
   
   Do you recognize the answer???


 The only remaining question is:

 Why is the country not run by a mathematician?


 Answer:

 Mathematicians have so much fun doing mathematics that they simply
 cannot be seduced to try anything else, at least not politics.


 vy 73 to all mathematically inclined  de         Helmut, DK2ZA




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