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Method & Theory

Re: Unbelievable Math Problem!
Steve

    If anyone is interested, here is an analysis that may shed
    some light if needed.1. Key in the first three digits of your phone number (NOT the
    Area code)

    Start with the first 3 digits of your phone number, we can
    use 123 as an example.
    You will also need a number that begins with the first 3
    digits of your phone number and has 4 zeroís at the end. If
    you multiply 123 by 10,000 you would get 1230000. You could
    add the last four digits of your phone number (we can use
    4567) to this and get your complete phone number:
    1230000 + 4567 = 1234567

    2. Multiply by 80

    This is a start, 80 X 123 is not 1230000, but keep in mind
    that if you multiply 123 X 80 X 250 you would get 2 X
    1230000, which would be easy to get back to 1230000 if you
    divided by 2.

    3. Add 1

    Donít worry, if you add 1 to 80 X 123 before you multiply by
    250, you can still back this out later when you subtract
    250. Adding (1 X 250) Ė 250 is the same as adding 0.
    So far, we have (123 X 80) + 1.

    4. Multiply by 250

    So now we have (123 X 80) X 250 + (1 X 250), which is the
    same as (2 X 1230000) + 250. Later we will subtract the
    250 and divide by 2.

    5. Add the last 4 digits of your phone number

    We could have waited until the end to add the last 4 digits
    to 1230000, but since we are doing it now we will have to add
    it twice in order to get back to it when we divide by 2.

    6. Add the last 4 digits of your phone number again.
    So now we have (123 X 80) X 250 + (1 X 250) + 4567 +
    4567,
    which is the same as
    (2 X 1230000) + 250 + (2 X 4567).

    7. Subtract 250

    Now we start simplifying back to our phone number. We remove
    the 250 from above by subtracting and get (2 X 1230000) + (2
    X 4567).

    8. Divide number by 2

    Then we knock it down to half, by dividing by 2 we get
    (1230000 + 4567).
    VOILA!
    1230000 + 4567 = 1234567.