jmcquown kirjoitti:

That was fun. I guess it works as long as you have 7 digits in your
phone number. Most do, but some don't. Some ppl here have 6 digits in
their hard line and ppl with old cell phone numbers can even have a 5
digit number.

Christine in Laitila, posting from work

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From: "jmcquown" <jmcquown@bellsouth.net>

I find it sad that "you won't be able to do this one in your head"
No wonder the rest of the world is kickin' our butts in technology
jobs that we are moving overseas.

try it this way:

2. think of the first 3 digits
3a. multiply times 8
 3a.(alternate) You can't multiply a 3 digit number times 8?
 ok. multiply it times 2. (double it)
 double it again.
 double it a third time.
3b. now tack a zero on to the end
4. add 1
5a. Multiply by 25
  5a (alternate) You can't multiply by a 2 digit number?
  ok. divide the number by 4 then move the decimal point 2 spaces
  to the right.
  5a. (alternate to the alternate) divide by 2 then divide by 2 again and
  move the decimal point 2 spaces to the right
5b. move the decimal point another space to the right
(if you can't do 6-9, go back to 4th grade)
6.  Add the last 4 digits of your phone number
7.  Add the last 4 digits of your phone number again.
  6&7(alternate) double the last 4 digits then add that to (2-5) [but this requires
  remembering two numbers, which can be confusing. At least for me it is]
8.  Subtract 250
9.  Divide number by 2

There, you just did it in you head. :)
And if you think about it, it should now be quite obvious why this works.

Says who? ;-)