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Posted By: pcgrav GAME: Math Trick - June 11th, 2005 at 11:10 PM
This came to via e-mail; it was neat so I thought I'd share!!! wavey

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?
Posted By: RugbyHukr Re: GAME: Math Trick - July 13th, 2005 at 09:49 PM
It is actually a simple equation.

1st 3 digits = X
multiply by 80 --> 80X
add 1 -----------> 80X + 1
multiply by 250 -> (80X + 1)x250 -> 20,000X + 250
add next 4 digits = Y
again = 2Y --> 20,000X + 250 + 2Y
minus 250 --> 20,000X + 250 + 2Y - 250
divide by 2 -->(20,000X + 250 + 2Y - 250) / 2

so, 250 cancels --> (20,000X + 2Y) / 2

divide thru by 2 --> 10,000X + Y

So, you get the first 3 digits (X) multiplied by 10,000 to give you 4 zeros at the end. Add the last 4 digits (Y) to get your phone #.
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